Species to Soundscapes: Build Ecoacoustic Biodiversity Monitoring Programs
Watch on YouTubeVideo summary
Building practical ecoacoustic biodiversity monitoring programs requires shifting focus beyond the intensive development of classification models to address often overlooked foundational steps that ensure long-term success. Experts emphasize that defining clear management goals must precede all other decisions, influencing equipment selection, spatial placement, temporal schedules, and sampling rates. While the community has traditionally prioritized training classifiers like BirdNET and PERCH using transfer learning techniques to identify novel species with minimal data, effective monitoring also demands rigorous site selection with proper controls, comprehensive metadata recording, and thoughtful strategies for handling storage constraints while adhering to technical standards such as the Nyquist-Shannon theorem.
The design of these surveys significantly impacts their efficiency and cost-effectiveness, particularly regarding sampling duration and frequency. Continuous 24/7 recording is often ideal initially to establish activity patterns, but duty-cycling—recording in frequent short bursts rather than infrequent long blocks—is frequently superior for detecting rare species while reducing data volume and expenses. Analysis of detection probabilities reveals that extending recorder deployment beyond thirty days yields diminishing returns; however, even a week-long setup can provide feasible guidelines for identifying significant occupancy declines. By utilizing high score thresholds to avoid false positives in occupancy modeling, researchers have successfully mapped distribution patterns over time, showing that acoustic methods often offer equal or better estimates compared to traditional point count surveys, except perhaps for certain nocturnal species like hawks.
To maximize the utility of these programs, it is essential to move beyond simple presence-absence data by calculating detection rates standardized against recording effort to reveal seasonal activity and correlate with survey counts. Case studies illustrate how these principles are applied in real-world scenarios, from collaborations with Indigenous ranger groups monitoring threatened species and cultural burning impacts to projects on Christmas Island National Park that adapted schedules for endemic birds and flying foxes using few-shot learning models trained on single voucher calls. Although correlations between acoustic metrics and actual abundance indices may not be perfect, both methods serve as valuable indicators of population stability when combined with pilot studies that optimize site numbers given logistical constraints like power availability.
Looking toward the future, ongoing work aims to refine these programs by leveraging detection probability models to reduce false negatives caused by overly high scoring thresholds. As machine learning recognizers improve their ability to distinguish between genuine bird calls and mimicry by species such as lyrebirds, acoustic monitoring continues to prove its worth in revealing complex ecological patterns that traditional methods might miss. The integration of existing data repositories with advanced modeling techniques allows for robust occupancy assessments even when resources are limited, ensuring that biodiversity conservation efforts remain both scientifically rigorous and practically sustainable across diverse environments.
Read the full video transcript
Welcome and thanks for joining us today
for a webinar on practical eco acoustic
methods for monitoring biodiversity. My
colleague Andy White will introduce our
invited guests.
>> Lynn Schwaskkov um distinguished
professor and memorous college of
science and engineering at JCU. So uh
we've also got um Dr. Sharon Brody and
Dr. Sebastian Hoer um speaking today. So
I will hand over to Lynn to start the
webinar.
>> Hi everybody. Thanks very much for the
opportunity to present this um webinar
and thanks to the ARDC. Um what we will
be talking about today is building eco
acoustic monitoring programs and we're
going to focus on um perhaps unusual
parts of um of these kind of programs,
unusual bits that people don't think
about. I hope so. Anyway, so I I imagine
everyone here knows that passive
acoustic monitoring is where you just
put automated sound recorders out in the
bush and you capture the entire acoustic
landscape of an ecosystem, just
everything that happens.
Um, and so that includes the geophony,
which is the wind and rain and
earthquakes and lightning and things
like that. Anthrophony, which includes
planes, trains, and automobiles. people
talking, things like that. And the
biophany, which is all the animal
noises, birds, frogs, mammals, insects,
everything that makes noise. Um, and of
course, we know that biophany can be
analyzed to measure biodiversity. And
that's what we're going to be talking
about today.
So, what we're trying to achieve is
something like this. We've got um I
don't know, can people see? Maybe I'll
get rid of him. Um, so what we're trying
to achieve is this. We got biological
reality or something like biological
reality out there in the world and we
want to make management decisions from
the information we get from ego
acoustics.
So that we should all agree on that. Um
but there should be a lot of steps in
between biological reality and making a
management decision. And today what I
want to be talking about is these steps
in here or what we are all going to be
talking about is that
I think what has happened in the eco
acoustics community is that there's been
an intense focus on the orange step here
uh which is why I made this big circle
orange. Um there's been an intense focus
on recognizer or classifier building and
the outputs from those and how good they
are and people have become really really
heavily focused on that and I think that
in order to build e uh eco acoustic
monitoring we need to think about these
other steps a bit more and so that's
what we're going to be focusing on today
and I think the reason why people have
focused so heavily on recognizers is
because there's a general perception
that vocalization detection algorithms
rely on vast amounts of training data.
And so therefore, training a model is
really hard and difficult to do and
difficult to achieve. You can only do
one at a time and it takes ages and all
that kind of stuff. And so I think that
now we've got a few new methods that
allow us to approach this. And I'm not
going to this isn't going to be a
methods talk, but you may have heard
about fshot transfer learning or
something like that. There's a paper on
it here by Jacuzzi and Olden. If you're
interested, that's where I got this sexy
graphic. Um, and so what we have is we
have models now which are kind of like
large language models but for birds and
they include bird net and perch. And
they include an awful lot of species of
birds now. So you can actually just
often search for a call within these or
get a call and get that call identified
right away. So we can already do that
for a lot of things. It's not perfect,
but it does work reasonably well. It
especially works well in Europe and
North America. There are species missing
from these models. So there are species
of birds that are not present,
especially in Australia. Um, but you can
also use these models to detect novel
signals. So you can get wind and rain,
insects, amphibians, mammals, other
stuff. And in my lab, we've been using
large CNN's, these bird net and perch
for detecting reptiles, mammals
including deer and other things, frogs
and insects. I've put whales here
because other people have used them for
whales. So the point is is that you can
put a sound into these models and
quickly create a recognizer for a model
that is for a sound that is not already
in the model. And it works like this.
You take your sample call and you only
need one individual sample call and it's
usually not a bird anymore. Although it
could be a bird that isn't in there.
Could be an insect, could be a mammal,
could be an amphibian. You put it in
there into the birdet algorithm or the
purge algorithm and it breaks it. You've
got a 3se secondond sample call. It
breaks it up into a feature set of 1,024
numbers that describes the sound that
you've put in there.
That's an example of a frog sound if you
heard it. I'm not sure if you could hear
it. Then you take all the rest of your
audio and you chop it up into 3se
secondond segments. You put it through
birdn net or perch and it creates
feature sets of 1,024 numbers or up to
1,024 numbers for all the rest of your
sound samples.
And then there's the frog again. And
then you situate your sample call. So if
you imagine all your audio looks like
this, your sample call is here. Okay? So
all your audio is described in a
1,024dimensional
space and your call is here. And then
calls that are close to it in that space
tend to be that species or something
like that species which allows you to
build a model that looks like this. The
distances here are ukitian distances.
>> Okay? And so you can line up all the
sounds um that you get on in your by
distance and you can I guess I can leave
that there. You can validate them and
you can see that sounds that are close
in uklidian distances between 16 and 17
in this case are yes they are your
species and there's ones that no are not
your species. Okay. And that allows you
to create a um threshold distance and
you can start thinking that everything
less than that distance is your species.
So you can build a a recognizer very
quickly using a a logistic regression
GLM and just do it fast. So we can do it
fast. So you don't need to have millions
of tons of of um data. You don't need to
have millions of of sample calls. In a
way, it's a way of finding a lot of
sample calls in your data and allowing
you to build a recognizer quickly.
So, when we are doing monitoring, now
what we need to think about is all these
other steps. Okay. So, um you may be
monitoring a rare threatened species.
You may be monitoring a rare invasive
species. Now, this one's especially
rare. No one's ever heard of the
sevenlegged gecko before. Um this is
thanks to Chat GTP. But anyway, all
invasive species are rare when they're
first arriving. And so you may want to
detect them um when they're first
arriving. And so you may want to detect
an invasive species when it's rare. You
may want to detect common invasive
species because you're trying to control
them and you want to see if you're
having any effect in their decline or
you want to know which times of year are
they most active? All kinds of things
like that. Or you want to maybe detect
the whole vocalizing community. And I
think we can do that now using the
technique I just told you about. So I
think one thing we should think about in
Australia is monitoring common native
species because we can do that easily.
Everyone who's got eco acoustic
recordings has got lots of examples of
native species and their activity on
there and it would be worth thinking
about noticing those species and seeing
if they're declining. Excuse me.
>> [clears throat]
>> So once we know what we're doing, what
we're trying to measure, we then have to
decide what do we need to know and we
need to decide whether we only want
presence absence. Now people have
focused in general on the fact that
presence absence is what we need for
them for uh or all we get from acoustic
monitoring. But that's not really true
anymore [snorts] because now we can
record for long periods of time. we can
get vocal activity and vocal activity is
often positively related to the numbers
of animals. And so you may be able to
get population size or an index of
population size. You need to decide when
you're going to record because you want
to record when they're most active if
you're looking at activity as a gauge of
when of how many there are. Um and you
may want to measure overall diver
biodiversity. So you need to make a
decision about what you're measuring or
which things of those you're measuring.
Then you need to go out and you need to
sample. I'm I'm adding a comment here in
that make sure you record metadata,
especially where and when the recorders
were placed because many recorders don't
do a very good job uh recording that
they've been moved. So, u make sure you
record where and when you put them
there. But think hard about your sites,
okay? Include controls. Don't only put
recorders where you think you'll hear
animals. include places where you don't
think you're going to hear them just in
case you do hear them or if you're um c
if you're creating an intervention. If
you're controlling something, you want
to know what's happening in the places
you're not controlling them. Are you
actually having an impact or are they
just declining because of seasonality or
some other thing, less food around? So,
you need to think about where you're
going to put your recorders with respect
to what you're trying to achieve with
management.
Don't assume your animal only vocalizes
at certain times. A lot of birds that
are supposed to be dal vocalize at
night. A lot of frogs that are supposed
to be nocturnal vocalize during the day.
We can you should really consider
recording 24/7.
And you should think about schedules.
Schedules may not be necessary at all
because we can store a lot more stuff
than we used to be able to. Uh but if
you are going to um sample, you may want
to sample for instance 20 minutes an
hour every second or third day rather
than just during the time that you think
your animal's going to be active.
There's a bunch of advant advantages to
that. And I'm introducing Dr. Sebastian
Hoer who you saw at the beginning. He's
a post-doal fellow in my lab. He's
working with the Department of
Environment, Tourism, Science, and
Innovation in Queensland with indigenous
ranger groups to help de develop
monitoring programs that um do what the
rangers require. So, he's helping them
develop questions and designing
sampling. And that's what he's going to
be talking about today.
Okay. Recognizer outputs. Those are the
orange ones that I told you were not
that important anymore or not not um not
deserving of laser focus is what I would
say. So classifiers and recognizers are
of course important. I'm not trying to
say they're not. Um but we need to think
now about balancing precision and recall
because for the most part for biological
recognition we need to prioritize
precision. So you need to think about
how much precision and recall you need.
For chorusing species that call a lot.
You don't need precise recall. You don't
need very high recall because you don't
need every single call. you're going to
hit a lot of the calls in a in a chorus
and so you don't need every single call.
And for presence absence, which some of
us are still trying to do, then um you
also don't need very high recall. You
just need very precise um um well, you
need precision.
Okay. So, um then we need we have our
our um our metrics that we're going to
create. And so, we use detections for
occupancy estimates over here. So that's
where we need high precision. That's
presence absence at a site level. And
now in my lab, we're working more with
activity. So what's the relationship
between activity and population size? So
if you have um surveys that tell you
population size, you can compare them
with activity and you can see if there's
a relationship between activity and
population size, that might give you an
index of of um of numbers of
individuals. And we can also get
community composition from species
lists. Of course, that's easier with
just hits or precision. And that's very
powerful because you can record for a
long time and so you can get everybody
in the community uh over the course of a
year or a couple of years.
And Sharon's going to be talking to you
today. Um she's a post-docctoral fellow
in my lab as well. She's been working
with NESP and also Parks Australia
building a monitoring program for the
woodland birds on Christmas Island. and
she'll talk to you about sampling and
occupancy and activity and how we're
using those to build a monitoring
program.
So the last thing we do of course once
we've got our measures is we can start
making ecological inferences. We can
figure out whether occupied sites are
increasing or decreasing. Are there
fewer occupied sites because that's bad.
Uh are there more occupied sites? Maybe
if you're looking at an invasive species
it's um it's it's bad too. Is activity
increasing or decreasing? And what does
it mean? We have to know the difference
between seasonal activity and not
seasonal activity. Um and when like
yearly is there differences in how many
how much activity there is. Are numbers
of individuals or our abundance proxy
increasing or decreasing? These are
important things to know. And our
interventions working and maybe we can
start looking as I said at the
abundances of um of common species.
These are not common species. I don't
even know what they are. But anyway, we
can look at the abundances of these of
different species that we haven't been
thinking about at all because we have
this data now. And the idea is that we
can use information to make better
management decisions, which is what we
all want, I think, or what a lot of us
want.
Excuse me. The key takeaways from my
talk are don't obsess about having loads
and loads of training data. Good models
can now be built fast for lots of things
using only a few sample calls. Even just
one works.
And don't obsess about recall because it
can be low for lots of the monitoring
tasks that we need to do most of the
time.
But do think about what is it exactly
that you want to know and how are you
going to best place your recorders,
record, do everything else to find that
out. how best you're going to sample to
answer your question to really answer
your question. What inferences can you
safely make from your data? Can you
actually infer something about activity?
Can you infer something about numbers of
individuals? Things like that. And how
will you use it to manage
um how will you best use it to manage?
I think we're moving on to Seb now.
>> So yeah, thanks Lynn for that. Thank you
all for tuning in and coming to this.
So, as Lynn alluded to, monitoring is
very different things to different
people. And I wanted to start by giving
more of a general overview of so what
considerations are important when
designing an eco acoustic monitoring
program and then dive a little bit
deeper into an acoustic monitoring
project we established in collaboration
with um First Nations Ranger groups
across Queensland.
So, I'll start with the more broad um
considerations. So the most important
thing when you're trying to uh come up
with a with a design is just figuring
out what the goal is of the whole thing
because the survey design is entirely
dependent on identifying a really clear
survey or monitoring goal. So are you
targeting single target species or is
the whole community so biodiversity is
what you're after? Are you looking at
aquatic, terrestrial or boreal species
or all of them? Are you interested in
species richness, vocal activity,
occupancy, habitat use? Um, also, is it
a long-term monitoring project or is it
more like a short-term biob blitz that
maybe gets repeated every once in a
while?
Um, do you have any prior knowledge of
the targets sounds that you're really
interested in? Um, for example, do you
know anything about the activity
patterns or vocal activity? You know,
what is it like during the day? What is
it like over the whole year?
Um, do you know anything about habitat
preference or home range? Do your
species or your target um sounds do they
move around a lot or are they more
stationary at a particular location? Um,
also what kind of recording equipment do
you have access to? Are you able to get
sort of more long-term audio recorders
or is it more of the smaller, cheaper um
short-term battery powered audio
recorders? Yeah. Similarly, you know,
what kind of microphones do you have
access to? you know, how many SD cards
are you able to get and what is the
storage capacity of those? And yeah,
again, with the audio recorders, are you
able to get solar powered devices or is
it entirely dependent on battery? So,
all of these are sort of yeah, come some
of those really important considerations
to begin with to even start thinking
about designing it cuz when you survey
or when you're thinking about the survey
design, um the target sounds, they're
crucial because they will determine all
these other considerations for the
survey design. um you know how many
recorders do you actually need is is
obviously often the starting point and
then where are they placed? So the
spatial considerations where you putting
them um how many do you have to get
where how do you replicate the placement
of those recorders? Uh you got to think
about the detection distance of each of
those recorders and what might influence
the detection distance because of the
you know the habitat for example. Um
again knowledge on on the habitat using
the home range of those species. If
they're stationary at a particular
habitat um uh structure then maybe you
need to only record there. Um and then
there are temporal considerations. So
how long can you actually deploy those
audio recorders for or do you want to um
what's the recording schedule like? Are
you going to do continuous or you going
to duty cycle your your recordings?
What about the maintenance protocol? are
you going to be able to maintain those
audio recorders regularly and how often
can you do that and do you have any help
doing that? Um the sampling rate is
really important obviously um to try to
figure out what yeah what frequency
you're going to be recording in. Uh and
then there are considerations on the
data storage you know how much data can
you actually store and you have access
to long-term data storage um how are you
going to sort of wrangle or or um access
that data and how you going to analyze
the data. And to begin with, it could be
really useful to start with a pilot
study to understand your survey design.
Um, where you also maybe get some
information about the species presence
in your audio recordings. And you might
get some information about noise
pollution. Maybe some anthropony with
some, you know, human-made sounds that
are really disturbing uh the recordings
in the particular areas. You might have
to actually move it or you might get
some information about the habitat
features that might impact your
detection distance. you're not really
getting any recordings or any sounds
from the the place you're actually
interested in because the the habitat
features are are um are not yeah are
sort of impacting that.
Um so for the spatial consideration or
for the recorder placement there are a
couple of really sort of common ways of
sampling. There's sort of your
systematic sampling where you're
sampling at sort of fixed intervals
across a whole area. Uh it's probably
the easiest design because it's you know
those fixed distances you know the space
between them so it can be easier to
navigate that in the field and deploy
them but you may require more samples
and they may be less representative. As
you can see in that little graphic there
that yellow habitat doesn't actually get
sampled because of those fixed
distances. So you might miss out on some
some um habitat.
And then there's stratified random
sampling. So that's when you are
selecting the group. So in this case
those four different habitat types and
then you randomly sample within them. Um
that sort of ensures representation of
all of those relevant groups but it
requires prior knowledge and you may not
represent the groups very well because
if it's random you might cluster some of
those points and as you can see there
some of those points are overlapping.
And then there's uh stratified
systematic sampling. So again, you're
kind of designating particular groups
beforehand um and you're putting a
number of fixed samples within and you
you are representing the groups and with
a more even coverage that way. But
again, it requires prior knowledge and
maybe even coverage is not possible
depending on what kind of um landscape
it is and what what those habitat
features look like. And then there's
purpose of sampling. So that's where
you're sort of selecting um the sampling
based on assumptions. So you are um
really highly efficient for a specific
purpose. So let's say you wanted to
sample creek lines. So you're just
selecting the creek lines and you're
sampling right along them. Um which
obviously requires certain assumptions
and prior knowledge and it introduces a
bias because you're only sampling that
particular habitat type or that
particular um group.
And then for the temporal considerations
um particularly schedules for the
deployment length uh that is really
important to figure out because
obviously will determine the type of
recorder because you know some recorders
are um going to be able to be deployed
for longer periods of times and some of
them will be more shortterm. So figuring
out how long you can leave those audio
recorders out there whether that's many
many years or just a couple of weeks at
a time um is really important to figure
out what you can actually get. Uh yeah,
as I said, maintenance protocols. Is it
actually regularly accessible? Are you
going to be able to go there and switch
out batteries and SD cards and check on
them for damages and and whether they're
still functional? If you can't, then
maybe a long more long-term um option
with the solar panel may be maybe more
suited in that case. Recording
schedules, whether you're doing
continuous duty cycles and again a pilot
study could be super useful to
understand that sort of temporal
considerations as well. um you know
identifying potentially seasonal calling
windows uh looking at DL patterns of
activity uh and then sort of weather
dependent activity
uh more specifically for the temporal or
for the recording schedules uh the
continuous recordings obviously you're
recording all the time and therefore you
have a higher chance to detect cryptic
or rare species
uh and you're getting a high resolution
data for seasonal and deal activity
patterns
which he can then potentially link to
environmental variables to get some um
answer some interesting questions. But
obviously it produces a large amount of
data and there are higher costs for
those recorders and for the maintenance
cuz you have to swap that out all the
time. Those SD cards for example.
Now GD cycle is where you record a
certain number of minutes per day and
then a certain number of days per year.
And that way you're lowering your chance
of detecting cryptic or rare species and
you're potentially getting a low
resolution data for those um
environmental links, but you're
producing more manageable amounts of
data and you might have a lower cost for
recorders and maintenance and also
longer battery life uh which enables
also cheaper recorders.
Now for the GT cycles aspect, um the
best way you can do this is obviously as
long as possible, but more importantly
as frequently as possible. So doing half
the time if you're recording 1 minute
on, 1 minute off is better than 30
minutes on, 30 minutes off. And you can
see this little um figure here from WID
in 2024 where they looked at the mean
difference in vocal activity rate
between continuous uh recordings and the
GT cycle recordings. So on the y- axis
here, you see if it's at zero, it means
that there's basically no difference
between duty cycled and continuous. And
if it's up all the way to 12 here, it
means that um the duty cycle there's
there's a huge difference. Um and on the
x-axis the coverage. So half the time, a
third of the time, a sixth of the time,
and so on. And within those brackets is
sort of the frequency. So 1 minute on, 1
minute off, 10 [snorts] minutes on, 10
minutes off, that sort of thing. And you
can see that um even if you're only
sampling a sixth of the time, if you're
doing more frequently, so 1 minute on, 5
minutes off, you're actually getting a
better result than if you're recording
half of the time, but 30 minutes on, 30
minutes off. So more frequently is is
really important. Um but ideally,
obviously, also as long as possible.
Now, for the sampling rates, um it's
kind of obvious, but we want to make
sure that, you know, we're we're getting
the frequency of the things that we're
interested in. And a really important
thing to consider here is that sort of
Nyquist Shannon theorem. So that sort of
determines that the sampling rate must
be at least twice as high as the highest
frequency of interest. And that's
because you need two sampling points per
cycle to catch that crest and the trough
um to accurately represent each of the
sound waves. And that means if you're
interested in let's say a bird at 3 kHz,
you want to make sure that you're
recording at at least 6 kHz to capture
that bird.
Now, for the sampling rates, um, if
you're recording at around 22 kHz, which
is that green box here, you will be
getting, you know, most of the birds,
amphibians, reptiles, most mammals, uh,
most invertebrates, and a few bats. If
you then up it to 44 kHz, you're getting
additional bats and you're getting
additional invertebrates. And then above
44 kHz, um, you're in that ultrasonic,
uh, frequency range, and that's where
you're getting a lot of those really
high pitch vocalizing bats that you
can't hear. Um but obviously the higher
your sampling rate is the more data
storage is required. So that's that's an
important thing to consider.
Okay. So that's sort of the more general
considerations or important
considerations when you're trying to
come up with a um eocic monitoring
project. And I wanted to sort of dive
into um what we've been working on which
is that uh listening to country uh
project which is a collaborative
partnership designed to empower
indigenous ranger groups by sort of
bridging the gap between acoustic data
collection and the actionable actionable
ecological management outcomes. Um and
what we're trying to do is we're
building capacity for acoustic
monitoring. So sort of enabling the
rangers or teaching the rangers how to
use uh acoustic devices and think about
what needs to be in place for this to
happen and add this as a tool to their
toolkit um in order to look after and
care for country. And it's all based
within that brightway science approach
which um if you haven't heard of it is
defined as a collaborative process of
bringing indigenous and western
scientific knowledge and methods
together to create an ethical,
productive and mutually beneficial
research. And as the mach people put it,
it's an exchange of knowledge and a
chance to learn based on mutual respect,
responsibility, and connectedness. It's
a collaboration that recognizes the
value each group brings to a project
when there's a shared interest in the
outcomes.
And um yeah um we want to make sure that
we work in close partnerships with each
of those groups and co-design um and
execute monitoring projects that meet
the specific objectives of those groups.
And the foundation is really a
commitment to a transparent and adaptive
and deeply collaborative process to
ensure that the rangers needs um yeah
ranges needs are are met and they
prioritize sort of every step that
prioritizes every step of the way. Um
and at the moment we've got these four
groups here, the Junja Norman B Yman and
Tagalaka that we're working with really
closely. um as [clears throat] well as
we're in convers conversations with um a
bunch of other groups and hopefully have
uh many more in the future. Uh there are
a bunch of different things that a bunch
of different objectives that the groups
are interested in. Um there's an
interest in threatened species detection
particularly ghoulian finches and golden
shoulder parrots are really really
important and of interest to the groups.
uh feral animal control and management
and in particularly what the impact of
that is once you start controlling those
uh fereral species
um the impact of preservation and sort
of restoration of water bodies on
biodiversity. They've been uh really
badly impacted by angulates and so you
know once you actually protect those
water bodies what does that mean for
biodiversity?
uh gathering evidence for the success of
cultural burning practices. Uh as well
as assessing biodiversity in areas that
are really difficult to access regularly
like on top of mountains and and yeah
really far um hard to access places. And
then as a public engagement tool as well
um to get sort of the younger generation
interested uh ongoing and going back out
onto country and getting involved. So
you can take those sound clips and
potentially go into classrooms and then
show them what healthy country looks
sounds like um to get them wanting to
come out and then help.
Now, so far um we've had u the chance to
deliver sort of hands-on training to the
ranger groups uh on sort of the
principles on acoustic monitoring and
recorder deployment, equipment
maintenance and the data management
workflows uh all in order to establish a
really an ongoing acoustic monitoring
projects where the ranger groups are
able to do everything from start to
finish by themselves. Um it's really
important that we make sure that the
sort of um data transfer analysis is
really transparent and um can really
easily be followed by the groups and we
utilizing um EOS that open acoustics um
platform to sort of store the audio data
have it accessible and then analyze it
as well.
And ultimately the goal is to build a
useful tool to visualize the audio data
um really simply so that the groups can
really see potentially when their target
species uh are active and where they're
active. So get information about sort of
space and time um when things are are
yeah are around.
And again this is all based um on the
rightway science approach. So it's
really important that um we're very
transparent. there's a lot of
communication and collaboration going on
and a knowledge exchange. Um, it's
really important to build these
relationships based on trust and mutual
respect and ultimately the ranger groups
are conceptualizing the research ideas
and they're there to collect data and
they're currently possessing the skills
to successfully deploy and maintain
audio recorders but sort of the
specialized partners required to help
realize the full potential of the data.
And that's where we come in where we
support with the data management and the
analysis um process. And then ultimately
we want to report those scientific
findings together and make sure that the
research um as well as management
outcomes are met.
Now if we're running through the
conceptual conceptualization uh using
one of those objectives I mentioned, it
kind of could look like this. So you
think about the goal. The goal in this
case is to figure out um if biodiversity
is potentially increasing at those water
bodies after you're controlling and
excluding excluding angulates from uh
from water bodies. And so in this case
you might be interested in a whole
community target with various life
histories and um potentially looking at
species richness and vocal activity to
begin with. Now for that you probably
want to get a sort of long-term audio
recorder option. So something with a
sonar panel that can sit out there and
record audio data um continuously
particularly in regions where you might
not be able to access it maybe due to um
weather like the wet season where you
might have to have these devices out
there for months on end and no one is
able to check on them and make sure that
they're still still functioning and
recording then um so yeah continuous
recordings in this case we're interested
in want to make sure that there's some
regular maintenance schedule uh set up
where um groups are able to go out there
and and two um checks on the recorders
and the SD cards. And in this case,
we're using purpose of sampling because
we are interested in water bodies,
particular water bodies.
Um want to make sure that we have
multiple copies and that long-term data
storage is uh is um uh given. So we
create you know local copies as well as
in our case we're using echosounds for
cloud storage and then we're analyzing
the audio data and machine learning um
and have uh extensive uh expert
validation to make sure that those
detections are actually true detections
and then yeah potentially develop uh
call recognizers for particular species
to make sure that you know future audio
data that we're getting is going to be
more effectively and um quickly
analyzed.
Thanks, Seb. So, yeah, I'm going to be
um conscious of time, so I might give a
a very overview at the start, but yeah,
I'm Sharon in in at JCU in Townsville.
And in my post-doal research, we we've
been working with uh Parks Australia and
Christmas Island National Park to
explore what role acoustic monitoring uh
might might have for the species
conservation and management. Um using
Christmas Island National Park as a test
case for national parks generally. Uh
this is a a NESP um project supported by
the um Australian government. Um and
I'll give you a brief overview
background of the project and the steps
we've taken to build a monitoring
program and some opportunities and
challenges we faced along the way.
So um if you don't know Christmas Island
um it's Australian island territory in
the Indian Ocean about uh 350 km south
of um Java. It is renowned for its high
species endemism and um of course its um
famous red crabs and the red crab
migration. Um and Christmas Island
National Park covers about 63% of of the
island managed by Parks Australia. Um
and it's a good test case for
establishing an acoustic monitoring
program because it's an isolated island.
There are relatively few species there.
There are about 22 resident breeding
species of bird and as and one species
of mammal at Christmas Island fly
blinding fox.
Um so building this program I'll just
introduce the our target species. So we
have six um six forest bird species that
we're targeting initially in this
acoustic monitoring program and the
flying fox. And I guess it's just
important to point out why we've chosen
these species. So they're all endemic to
Christmas Island either at the species
or subspecies level. Um so they're being
in it being in an island habitat, their
species of of concern being endemic and
four of the bird species are um are
currently vulnerable or threatened. The
Christmas Island flying fox is um
classified as critically um endangered.
Um and so you'll meet these birds a bit
more later on. Um and so I came up with
my own hierarchy of what were the what
are the questions that what do we want
to know in our um acoustic monitoring
program and um starting from a broader
um overall question of what we really
want to know is in monitoring are the
species population stable or are they
increasing or are they declining? But to
get there we need to using acoustic
monitoring data we need to know what are
we going to measure. Um so um can we get
metrics like sight occurrence, presence
or absence out of the acoustic data and
vocal activity so using detection rate
but then we have further more detailed
questions from there. Okay, if we can
measure um we have some questions about
how reliable is this method going to be?
Can we reliably detect these species
using acoustic data? When should we
record? How many sites should we record?
And is vocal activity related to is it
is it a good reflection of um abundance?
Um and so just an overview of our um
actual recording um regime. We recorded
at about 80 80 sites give or take you
know depending on the project's been
going for over two years now. So
sometimes you know recorders are in are
in and out out of commission. Um
uh we commenced back in May 2023 after a
pilot program. Um the number of sites
generally became restricted by the
number of recorders that were available
um and working. Uh I we started with a
few more in the in the pilot site but
that was whittleled down. We used barlt
recorders from Frontier Labs down in the
left hand leftand bottom picture. Um
there we put a um a mesh over the
microphone because we had problems with
something, we're not sure, chewing the
microphone um phone. Um and we also had
at the start five solar bars. So that's
a solar powered bar um there which we
actually found worked well only if it
was out in an open habitat. It didn't
they weren't reliable in forest because
the you know power was quite
intermittent.
Initially we started recording 24/7. Um
but we found that um after a couple of
months that uh we the project just
didn't have the resources to be able to
go out and service and change the
batteries um regularly enough. Uh
running the bar LTS on battery power. Um
they ran out of power after about a
month of continuous 24-hour um
recording. So we changed that um
schedule down to 20 minutes per hour on
the hour all day. so that um we could
then get 3 months um recording out of
each recorder. And we wanted to because
we're recording multiple species and the
hawk being a nocturnal species, we
wanted to record across the whole day.
Um and then later in the project again
because of resourcing logistics, um we
changed that to every second day just
because of being able to get out to the
island, go around to all the sites and
change batteries. So we still had that
temporal coverage um over the over the
year. And the map there just shows you
the the generally the the um sites
recording sites that were used across
the island. So we wanted an islandwide
coverage.
Um and just to mention that what we do
with our audio when we collect it off SD
cards u it's uploaded to the ecoounds
repository which is uh was created and
is run by Qout eco acoustics research
Paul Rose Lab and um Anthony Trusinger.
Um and we upload it um from JCU using a
nice fast internet connection which is
um necessary.
It's not much luck if you don't have
one. Um and the ecos repository is
brilliant. It's good at um you know safe
storage. It organizes Anony's written it
so that it organizes your audio file
metadata for you. It does have playback
and annotation download functions. We
don't use that in this project because
it's a it's a big project. Um and now it
also has um in into it analysis
functions. So uh with the perch or
birdnet um classifiers, it will um
generate your embeddings for you and it
will soon be generating your um
classifier detections for you. So just a
note on that. Um and so the question
reliable automated call detection, can
we do it? Yes, we can. And so I'm going
to sort of skim over this because Lynn
did touch on um the the state of
classifiers where we're at at the
moment. But um all this great intense
work was done by Phil Iinsky at Qout at
the start of the project to build our
classifiers and we use the perch um CNN
model which is developed by Google
research. Um
and yeah as Lynn talked about it's it
uses that fshot transfer learning. So we
only needed to start with uh sometimes
one um training example of each species.
So we did collect some voucher calls. So
an actual you know um when you go out
and identify a bird and say yes I'm
recording you know the emerald dove.
This is it. And that's our example
training call. Um or for the gosh hawk
we had to go to xenoanto. We didn't get
any voucher calls on the island but the
gosh hawk is uh sometimes considered a
subspecies of the brown gosh hawk. So we
use an example call of CNO Kanto for
that and that starts the process that's
um building the classifiers improving
them through iterations. So you can use
those initial train examples to find
more training examples in your actual
field data to build really good um
classifiers.
Um and just some technical notes before
I go on it will it will help with my
next slide. The way the perch classifier
model works is it it segments the audio
into 5-second segments, analyzes that
and for each species model, it gives
each segment 5-second segment a
prediction score as to how confident it
is that that 5-second segment has your
target species
and then what we do with that. So Lynn
also um touched on this before. uh we
have all these detections um having I
think at last count we have over 380,000
hours of audio and so if you work try to
work out you know how many 5-second
segments that is it's millions and
millions and so obviously not all of
those segments are going to contain your
target species but they're all analyzed
and they all get a score by the perch
model. Um but you want to count
detections. How many of these um call se
audio segments have your um actual
species in them calling in them. And so
we use this logistic regression approach
to determine a score threshold. So we
want to basically only you know we want
to chuck out all the segments that
aren't our species um and um count how
many detections of our species we've
got. So you validate a sample of of
audio segments across a range of scores.
do a logistic regression um that gives
you curves like this. And the one on the
left is the uh uh call um dete
classifier for the thrush. And ideally
you want it to look like this. So when
you have um uh the data dots down the
bottom are negative examples. So so
segments that don't have the species. Um
you want that nice curve where it's you
know can ideally almost get separation
between your ne your negative and
positive examples. Um and the hawk there
shows an example of where um we can get
a score threshold that gives us um high
confidence of true positive calls but
we're still missing a lot of of calls.
Um but um yeah so talking about um what
I did with these detection calls firstly
I took an occupancy modeling approach
and an assumption of occup occupancy
models is that there are no false
positives. So we I had to choose a score
threshold that gave me a very high
confidence that I only had um true
detections in there.
Um and so that's often, you know, the
first question that you can address with
um this type of data. Um I've applied
the score threshold only looked at call
detections above the threshold and it
can give us a nice picture of where
where we're detecting our species. So
where do our um species occur, what
sites do they use? Um, and the nice
thing with acoustic data is if you have
long-term acoustic data, it's very um
it's a very rich source of of data. You
can aggregate it in different ways. So,
you can choose different periods. You
can aggregate, you know, months and
days. This is just um over the our first
year of monitoring um the sites that we
um detected the species at. And you can
see that even um just a couple of
examples that these birds are quite
widespread across the island. and the
emerald dub wasn't detected at some
sites, but the pigeon and a few of the
other species are detected just about
everywhere across the island.
[clears throat]
Um, so uh, one other question we wanted
to address was how does this acoustic
um, detection method compare with
traditional field surveys? Um, and I did
this using the occupancy uh, modeling.
So this is the um detection probability
estimates using occupancy models um in
that I did in R and I compared it with
um point count surveys that we did um uh
at at our sites. So we did these surveys
at our recorder sites um over two years
except for the hawk which was a
nocturnal survey done in the second
year. Um and I calculated the um the
occupancy and detection probability in
that same period. And I the takeaway to
this is that um except for the hawkowl
we actually get better or as good as
detection probability um using acoustic
modeling uh acoustic monitoring data um
and with acoustic data we get better
estimates so lower um smaller confidence
intervals which is um which is better
for occupancy modeling. We want um good
estimates.
Um and then so stepping on from this
what we did if you if you'll uh sort of
notice back here that the detection
probabilities vary. So detection of the
dove was and the goss are quite low um
but the other species are quite high. So
we wanted to focus on what were the
times of year that we could detect
better detect the emerald dove and the
gohawk because their detection
probability is generally low whereas the
other species are quite high most of the
year. Um so to be able to um you know m
maximize um the the monitoring
capability. So this is a temporal um
plot of the monthly detection
probability just from the acoustic data
to show us that you know there are
better times of year than in July and
when we did the surveys when the doves
were hardly calling they're very
seasonal um to give us an idea of when
when to record. Um and so from that what
I did was I did a power analysis. So I
used an approach where we can get uh use
an approximation equation to calculate
the the statistical power uh and the aim
here is to detect a decline in occupancy
from one monitoring period to another.
So say from this year to next year u
what's the what's the power and what's
the effect size that we can detect. And
this was to um inform you know how many
sites do we need to record at uh how
many days do we need to record for um
and is it feasible and this is the
example for the emerald dove which with
its low probab probability of detection
is the most challenging one. I found in
all the cases that the advantage of
acoustic monitoring is because we can
record for extended periods of time. Um
you get better better power than just
doing a few surveys. But beyond 30 days,
you don't get much much you know extra
advantage out of it. Um but it's quite
um straightforward. If you're going to
put recorders out for a week, there's no
sort of extra effort just to leave them
out for another few weeks. But what this
is uh really showing here is that
there's some decisions to be made um
depending on you know how many what's
what what feasible as far as the number
of sites that you're able to monitor um
and what's uh what's an what's a
meaningful um effect size so occupancy
decline that you're wanting to detect.
So, say for example, if you had um um
100 um recorders and you had the
capability to record at 100 sites for a
month, um you could detect, you know,
let's just say a bit more than a um 0.25
decline in occupancy with 80% power. So
um it gives a real sort of guideline to
parks Australia for what kind of effort
they need and what uh what um size
decline are we able to um detect even
for this um uh dub that's difficult to
detect sometimes.
Um and so yeah moving on. So moving on
from occupancy um analysis looking at
using that vocal activity. So rather
than just reducing the data to presence
absence um actually looking at
calculating the detection rate. So
number of detections this is a plot
example of a number of detections um
each day standardized for the number of
hours recording. So recording effort um
and this is a nice example of the
seasonality in the emerald dub and the
low detection rate. Um the gray box
there shows a period where we missed
data because a lot of the recorders ran
out of power. So we were didn't have
enough um recorders uh going there. Um
yes. So that's just just to show a use
there of how you get really nice um
temporal activity patterns.
Um and moving on from that, what we also
wanted to know was does vocal activity
reflect survey counts. So again, we use
the survey data that we did in those two
two years, the um four four survey
visits at each site doing point counts
to see if our detection rate was a good
um uh you know, I guess if if it related
to the survey counts. Um and what we
found was there, you know, reasonably
good correlations between we've got
acoustic detection rate and the average
survey count in each in each year. So
each of these points is one site in one
year. Um and I guess it's important to
point out there that um even though you
know the correlations aren't perfect
that point count surveys um the counts
from those surveys they're you know not
a true reflection of abundance either.
So they're um an index of abundance as
well. So here we can see that the
acoustic detection rate as an index
correlates well with survey counts um as
an index and I think I've got yeah got
the other examples in there as well um
uh just showing that we can correlate um
uh the detection rate and so it gives us
a good um a good uh foundation that we
can use activity vocal activity as uh a
metric for monitoring to be able to
monitor if there's changes going on.
Um how do we go? Okay. And um yeah, so
from here what we're doing, we're still
exploring the vocal activity metrics. Um
I want to get into seeing if we can
reduce the false negatives. So using
more of the data at the moment, using
that, you know, really blunt threshold.
Um assures us we have positives, but it
also throws out a lot of that um uh you
know, um false negatives, I guess we
call them. So, um, detections that we're
missing because we're using that high
threshold. And, um, so there are ways
that we can, um, you know, use use
detection probability to use more of
that data. And then looking at, um,
power analysis again to be able to
detect changes in that vocal activity is
where we want to go with that. Um, and I
just want to acknowledge just some
acknowledgements there of who's been
involved, lots of people involved in
this project. Um, and that's me. I think
that's my last slide. So, I'm hoping we
got time for questions now. [laughter]
>> Oops. We all talked for too long.
Well, yeah.
>> Oh, um, you can go on for another hour
in my opinion, but I guess I guess I'm
not the boss of it. [laughter]
>> Liz, there's only a couple of questions
that haven't been, um, asked, but um, if
anyone else has any questions, feel free
to ask away. Um, can I also just say
that we can we can last beyond the hour.
So if you if people want to stay online,
I understand people are busy, but if
people want to stay online and are
desperate for an answer, or you can just
email us and we'll be happy to answer
you.
>> Yeah. Brilliant. So if you if you need
to run now, please um give us a question
and then and take off. Um but yeah, I'm
very happy to host people on for another
10 minutes, 10, 15 minutes to um follow
up on these. Um well, I'm going to start
with the one of the last questions which
um was
uh
which was about the standardizing effort
between point counts and acoustic
monitoring to do the occupancy modeling
and compare them. Sharon, I think you
started getting towards that and you you
you explored that in your later slides.
So, is there anything you'd like to you
could say about the standardizing the
effort between those two?
>> So, I guess when you say standardize, so
we wanted to compare the two methods.
So, the effectiveness of the two
methods. So, we did the surveys were
done within a five or six week period.
So we actually had a burer go out and do
surveys at all the sites four times
which is the general approach in
occupancy modeling. You you do repeat
surveys. So I just looked at at the
detections in that same period. So in
the so in the five week five to six week
survey period. So I got daily detections
um daily presence absence out of the
acoustic detections in that same period.
So we we wanted to do a comparison as
you know what's the results if you were
to use repeat surveys for occupancy
modeling or if you were to use acoustic
recording for occupancy modeling what's
the outcomes of using either of those
approaches so um uh so I guess you know
they are different methods so I don't
know if standardizing the rights is the
right word [clears throat]
>> um uh but it's yeah it's comparing the
methods to that
>> like my assessment of your answer is
correct. Um is that that's that's great.
Another question. Um I'm going to move
over to um one from Clara. For a project
tracking site level changes in the
population, sorry, for a project
tracking site level changes in
population composition across seasons.
Would it be sufficient to leave the
recorders out for a week at a time at
each site for each season, or would they
be better staying out for longer?
Um, I can probably take that unless you
want to answer it, Seb.
Um, it depends on your animal [laughter]
or whatever you try to follow. Okay. So,
um, a week at a time might be good if
it's a Christmas Island thrush and it
never shuts up. But if it has a seasonal
time that it calls or something like
that, then you need to have your your um
your recorders out at the right time.
Um, [clears throat] sometimes what you
need to do is record for a while to be
able to figure out what the right time
period is. So, when is that animal most
active? And then that way you can um you
can detect its activity each season and
you know when to record to do that if
you can only do it. So, we always we've
been recommending more and more to
people record 24/7 or do what Seb
suggested and record in chunks of time.
Um, but record for long periods so that
you at least initially get an idea when
your animals are active. Does that
answer your question, Clara?
And I'll Yes. Yes. We got a yep in the
chat.
>> Oh, great.
>> Awesome. Thanks, Lynn. Um, Andrew had an
answer for Sharon about um
talking about the Christmas Island
pipistral insectto virus in insecttoous
bat. Um, Andrew, would you like to speak
to that comment that you put in the
chat?
>> Yeah. Oh, well, um, it's just something
that's, you know, talking about
Christmas Island. And I thought, "Oh,
there was this little bat that went
extinct a long time ago." Well, not a
long time ago. 2009.
>> Yeah. Recently. And look, it won't be
the first species that's been presumed
extinct and then excitedly been
rediscovered sometime down the track.
Um, Bronato walabe is a classic example
of that. Um, but yeah, I just thought if
you're out there sticking monitors
around Christmas Island, um, and I know
you'd have probably have to change the
frequency um, settings on your devices,
would it be also worth running a
recognizer for that if you could create
one? There's got to be there's got to be
spectrographs because they were
monitoring for those bats using anabats.
Um, and yeah, so yeah, I just thought
you might
>> Yeah, there's lots of lots of
considerations. Yeah, because bat
monitor monitoring in in ultrasound is
is um you know yeah has a different kind
of approach. Um and I know they did back
at the time it went extinct. There was
some intensive
monitoring going on and that's generally
how they would monitor for um microbats
is using the um the specialized um
ultrasound recorders. Um and I do know
that it's the topic comes up every now
and then about whether it should just be
um tried again to see if they can be um
detected. But I do know at the time it
was when um the working group was
raising the alarm bells. They were
intensively monitoring and they
basically watched it go extinct pretty
much in the monitoring data.
They could see it going. Yeah. But yeah,
it it's not um you're not the only one
who um yeah brings brings that up. It is
an ongoing discussion, but it it's kind
of um yeah, it recording in ultrasound
um uses more power and more data
storage. um it's got a specialized so
it's it's possible but we have to factor
in you know that the file size is going
to get so much bigger and and um but
it's uh yeah and building a recognizer
yeah definitely feasible
>> yeah and actually following on from that
um I'll read out another um question or
couple set of questions from a
reflection from Clayton who says
logistics power data storage access and
labor for maintenance has been
repeatedly flagged tagged as a
challenge. Is this a real limitation
impacting research or management or is
it just a frustration that needs to be
accepted and contingencies put in place?
So Lynn started off answering they're
not a frustration. You just need to
optimize them so you get the answers
you're actually after. But uh Lynn and
others would you like to expand um on
answers to this [snorts] question?
>> I'm happy to Seb. Yeah, unless you
unless you want to. Yeah, like I guess
it is a real limitation, you know. It's
it's how many recorders you have. It's
how much money you have to drive, you
know, hire cars and drive around and put
the recorders out. Um uh and um you
know, some analysis shows that yeah, if
you had 300 sites, you could really, you
know, detect and monitor um really well,
but it's it's got to be it it's within
limitations of what's what's feasible.
That's just a practical, you know, um,
consideration. And some people might be
frustrated by that. I don't know. Or
some people might just accept it.
[laughter]
>> And often that's where like pilot
studies come in, right? Like you give it
a try, you record for a certain amount
of time, maybe with a certain number of
recorders, and then you realize, oo, I
actually need more or maybe I don't
actually need that many. Maybe I can cut
down. you know, like just going out
there and then as Lynn mentioned,
starting off with continuously recording
is probably your best bet just so that
you can kind of understand when things
are.
>> I'm after that. Once you really
understand when things are active, you
don't want to start off potentially
missing stuff.
>> Yeah, definitely.
>> I can answer that one. says, "Sorry if
this is off topic for the webinar, but I
was wondering if you can speak to how
well-developed the Acoustics Observatory
of Australia is. Would it be feasible to
use the existing recordings on there to
do occupancy modeling in well-developed
survey survey areas instead of
conducting new acoustic surveys?"
Yes, it would be brilliant if somebody
used the acoustic observatory to do
that. So, we have four recorders uh at
each site in the in the um observatory.
Um, and it's got and it has two that are
close to water and two that are further
away. These may not be perfectly useful
for you. They not may not be in the
right place for whatever it is you want
to look at, but it's certainly feasible
to check out the locations. Um, my
postoc has just published a paper a
different postoc slate Alan Anderson has
published a paper looking for every
threatened species that we could find,
threatened, vulnerable, all those sorts
of things that we could find on the
acoustic observatory. So, if you're
specifically interested in a threatened
species, you could look at that paper
and see whether that species is in there
and whether he found it. Um, if he
didn't find it, you could talk to him
about how hard he looked. Um, because he
looked reasonably hard, but he had 73
species to look for, so he didn't look
all that hard. So, um, hopefully, um,
that is helpful. Uh yes, you can
absolutely access all the data there and
you could look through it and you we can
help you look through it and facilitate
your use of the A2O. Absolutely.
Does that answer questions?
>> Awesome.
>> Might help you with what do you call it?
Um
pilot study for example.
>> Yeah.
>> Somebody called Tom has his hand up.
>> Yeah. Go for it Tom.
You'll need to unmute.
>> Thanks. Yeah, I was just trying to
figure out how to unmute that. Um, I
have two questions. Um just looking at
some of the data that you guys were
presenting and I um if with the
vocalizations, it was kind of making me
think of like how how do you deal with
um the same species um say a a bird um
making different types of coals. So a
territorial coal versus um some sort of
mating attracting coal. Um and and that
goes for different species too, but uh
yeah, primary interested in that. And
second, this is a little bit more of a I
don't know if this has ever happened
yet, but it's sort of maybe an
interesting hypothetical, but um what do
you think would happen if uh something
like a liar bird came along and um made
a bunch of different vocalizations in
front of one of these um
devices, listening devices? Would that
would you be able to tell if it's a live
bird versus the real thing?
>> Um, I'll answer I can answer those
questions.
>> First of all, um, we don't know anything
about broods. We work on frogs and
mammals and [laughter] and most of them
only have one call. No, that's true, but
it's also not not really correct. So,
what we tend to use for a lot of the
birds is things like contact calls that
they make all the time um and that are
are useful, but you can actually build a
recognizer with several different calls.
Um, and it does it doesn't matter. It
learns to recognize them just the way a
person does in a way. And so, it's fine.
You can use all the calls of a bird and
find it. It's nice to keep them separate
though because you might want to use,
for example, territorial sounds at some
seasons and you might want to use calls
at other seasons. that kind of thing.
Um, but [clears throat]
we do not specialize on that in our lab.
In our lab, we're focused on
identifying, finding things, and looking
at levels of activity. So, we haven't
done that. As far as the liar bird goes,
it's my understanding that people can
tell the difference between a liar bird
mimic of a call and an actual call by
that bird. Is is that true? I've seen
someone do that, so I'm thinking that
that's true.
Um I just wanted to say also that I just
shared the link in here um because
that's a question that we quite often
get with the li birds. Um there's a
paper um on the vocimicry of libertirds
and if you look at the spectrograms in
there there's a slight difference
between the vocalization of a li bird
and the animal that it's trying to copy
you know whether that's a kabara or
something. So the thing is more about
how much data do you have. If you have
enough training data, then you can
distinguish those two for sure. At the
start, you might not be and it might
actually pull out the same species, but
then it just attempt it depends on how
much data you have. But if you have
enough training data, if you have enough
of the liar bird vocalization copying
the cookabara and the actual cucara, you
should be able to tell them apart
because there is if you look at those
spectrograms in that paper for example,
there is a difference in the
vocalizations.
>> But it's not easy. And when we say
enough training data, it means you need
to have examples of the liar bird copy
and you need to have examples of the not
liar bird copy and you need to be able
to chuck them into your data and find
both of them and look at the difference.
So you yes, you should quickly be able
to build recognizers that tell the
difference, but it'll be harder than
building a recognizer for two different
species.
>> Wow, great. Well, those were awesome
questions, Tom. And I feel like now's
probably a good time to probably wrap
up. I would love to go into this another
time. So, please um uh if you are keen
to revisit this conversation um or
extend it on in any particular
direction, please get in touch with
Lynn, Sharon, Sebastian, myself, Andy.
Um I'm not an ecologist, sorry. just
butting and like talking about this
stuff cuz my kids are bur now and so I'm
so excited.
>> Um,
>> thank you for being part of this. It's
my
>> would like to thank all of our
presenters today for your your time and
diligence and sharing your expertise and
we just would like to thank uh the
audience and the great questions you've
given today and um we hope that we get
to see you in one of these series in the
future. So thank you very much everyone.