There was research on this in the very early days of VHF radio tracking. I presume what you are interested in is the period between audible bleeps vs the easeof detecting a mximum as an antenna is rotated to get a directional fix. If memory serves the optimum between battery life and ease of use was either an interval of 0.8s or a frequency of 0.8 Hz (so an interval of 1.2 s). The low end of your adjustment range would be midway between those two - the res tof the range would be very hard to use.

Hi Chittakon,

I think an 'ideal' optimization between transmission interval and battery life would depend on the application.  As I think Peter has indicated, longer transmission intervals could make it very difficult to determine direction, particularly on a moving animal. If you were not trying to find direction and/or locate the transmitter - maybe just detecting presence or absence - then a longer interval could work.  cheers

Choice of pulse interval on VHF transmitters really comes down to how mobile your study animal is and how complex the tracking environment is.

I have used pulse intervals down to 2 seconds on animals that spend a lot of time sitting still. This does save on power but if you are used to a faster pulse interval, it can be a real lesson in patience when you are trying to get an accurate bearing on the transmitter. For animals that are constantly on the move, don't even think about going slower than 1 second, particularly if the transmitter is likely to be intermittently blocked by habitat features.

Other ways of saving power can be to have periods when the transmitter is scheduled to sleep (when you are unlikely to be tracking) or to have bursts of pulses (say 1 minute on, one minute off).

Another important feature to consider is ensuring that the transmission has a stable pulse strength and frequency. There is nothing as frustrating as a transmitter that fluctuates in signal strength.

Hi,

I am using these for my current project:

Read "Amazon.in" on

Amazon.in

They seem to be of good quality and support offline SD card storage. These run on 5V/1A. You should be able to run them for about two days on a 45 or 50,000mAh powerbank.

There should be UK versions of these.

However, like all CCTV manufacturers (atleast the ones i checked), downloading the continuous recordings isn't as easy as plugging in the SD card into your computer and copying the files.  The video files are deliberately made hard to read. Everything is through their app. You can download events (movement/sound) captured by the cameras though.

Hi Paul, 

I just remembered another one for the list. @BethClark is taking some really cool environmental readings for seabirds - Gannets - basically to build a picture of their lives in 3D. She talks about it on her blog here.

A few excerpts: 

Electronic devices are attached onto the birds to record their behaviour: GPS, altimeters, accelerometers and dive recorders. The key will be to use multiple loggers on the same bird to record their flights in great detail. The GPS tracking project has been going on Grassholm for a few years now and we are building up a good picture of where they tend to forage.

The altimeters show the height above the sea, which gives us 3D tracks of the birds’ movements – very cool! The higher you are, the further you can see, but the more difficult it is to pick up scents from the sea. We will find out if these 3D help us pick out foraging behaviour and see how they actually find fish (and fishing boats) in a huge and seemingly featureless ocean.

Dive recorders show the timing and depth of the famous torpedo plunge dives, which will let us know when the birds have successfully found a fishing ground.

The accelerometers measure acceleration in 3 directions, showing even a single wing flap. This will help us to measure how much effort the bird are putting in when they travel and forage, which is very important for trying to figure out how they decide where to go. We will also be able to identify other behaviours, such as telling apart high-speed plunge diving from a slower dive made from the surface.

I think altimeters and dive recorders might be new ones for your list. Beth's here on WILDLABS.NET (and has promised a nice case study for our Resources area), so I think she'd be delighted to answer any questions you might have. 

Cheers,

Steph 

Hello again!

An interesting paper exploring the new technologies being used to study cetaceans has a section devoted to what they term high-resolution multisensor tags (page 4).

As with @BethClark 's work above, the questions that arise when studying marine mammals bring another dimension into what information we might require sensors to collect. For example: 

Among cetaceans, there are two suborders: Odontocetes (toothed-whales) and Mysticetes (baleen whales). In general, toothed whales and dolphins use high-frequency acoustics for interanimal communication and feeding. In the marine environment, where sight is limited, sound propagates extremely well and all marine mammals communicate primarily through acoustic cues. Similar to bats, toothed whales and dolphins feed via high-frequency sound production known as echolocation, where acoustic signals reflect off of targets and the returning echoes can be translated into information on the environment or potential prey. For many years, independent passive acoustic recorders have been used to study the vocalizations of marine mammals. However, the incorporation of acoustic recorders (hydrophones) into animal-borne tags has only occurred in the past 20 years (Fletcher, Le Boeuf, Costa, Tyack, & Blackwell, 1996). The information that is recorded on the sensors in these tags (e.g. acoustic, movement) can be used to determine the frequency and acoustic structure of vocal behaviours that occur concomitant with motor behaviour, for example, echolocation signals during feeding events (Madsen, De Soto, Arranz, & Johnson, 2013) or contact calling while diving ( Jensen, Marrero Perez, Johnson, Aguilar Soto, & Madsen, 2011). Echolocation ‘clicks’ and ‘buzzes’ have been used from animal-borne tags to study the foraging behaviour of a wide range of odontocetes, from the small harbour porpoise, Phocoena phocoena, to the largest, the sperm whale (Fais et al., 2015; Wisniewska et al., 2015). This information has provided critical data on the feeding depths, frequency, timing and prey types targeted by different species and the behaviours associated with foraging (Johnson, de Soto & Madsen, 2009). These insights into feeding behaviour have recently been used to help determine foraging performance and foraging ecology (Watwood, Miller, Johnson, Madsen, & Tyack, 2006), as well as the energetic consequences of disturbing this behaviour (Miller et al., 2009). These new data products are ripe for linking to conservation efforts such as the individual and population consequences of human activities disrupting these behaviours (e.g. the use of naval sonar and seismic surveys). We explore below the tools produced, as well as new ones in development, to forge these links.

You have already identified sound in your original list, but I think the use of hydrophones with tags is an interesting addition - an example that didn't immediately spring to mind (at least for me), when I thought about the list. 

Cheers, 

Steph 

In Press: Nowacek, D. P., et al., Studying cetacean behaviour: new technological approaches and conservation applications, Animal Behaviour (2016), http://dx.doi.org/10.1016/j.anbehav.2016.07.019

Hi Both of you, 

Just a quick note now. Very interesting articles and topics found and discussed here. In my work with biophysical aspects of cheetahs I will review these things you have written. Thank you very much. Followed here from the sidelines  

                            BR Henrik 

Depending on what you really need, you might have different options. I don't think collar/bracelet for great apes is currently resolved reliably, and could pose risks to the animals. Implantable transmitters are one option but more invasive. I think Chris Walzer (currently at WCS) has done some initial work on implanting orangutans (or gibbons), but that was quite some years ago. Others might have done it since as well. FWIW we have implanted captive chimpanzees with subcutaneous transmitters for other reasons and some have removed/damaged it, so that's a risk. Intraabdominal might be another (though even more invasive) option. 

Is  visual observation an option? This is well used in many species, though might be very costly/labour intensive. I have been involved in a project with howler and spider monkey where this has been used successfully, happy to put you in touch with them. 

If your questions is primarily absence/presence of certain individuals, you could also try DNA based methods? And someone suggested below individual ID from video/pictures, this has been done in captive great apes, so it is an option, but you still need to get the shots in the first instance, so probably not many advantages over manual monitoring methods. 

Our city-neighbours Robotto are a Drone AI-software company and have an ongoing animal tracking projects in Thailand, Australia, and Greenland (probably more by now) in co-op with WWF, using drones. 

Give them a look! I know Kenneth, their CEO, pretty well so can match you two.

A rough explanation of how the tracking process happens is:
A forest ranger brings a suitcase with a drone to a watchpoint, pilots the drone around the area for 30-50 minutes while monitoring detections real-time on the provided screen.

Have seen it live in Thailand, it was impressive! :)

In a recent call with researchers in Thailand. They have mentioned that they use passive chip readers to log data about chipped animals as they pass by.  

Hello @robbiemp  

My method may not be the best at the moment, but I’ll share the results from my previous tests. Here’s what I’ve tested: “DIY using SDR connected to a smartphone as a radio telemetry receiver.”

I have a VHF receiver that works with SDR and an Android smartphone. I’ve tested it with a VHF tag that I built myself, "My VHF Telemetry Tag Building Project From Scratch."

It depends on whether you need data or just audio. If you need data, SDR may not perform very well. But if you’re just after audio signals, it can work similarly to a regular VHF receiver. By using a Yagi antenna and connecting the SDR to the smartphone, it can work for any frequency range you want. I used 148-151 MHz, but you can use more than that.

Please understand that it works similarly to a commercial VHF receiver, but it may not be as good as the ones available in the market due to various limitations. However, it can still be used. I tested it with a Yagi antenna that I made myself (but if you already have an antenna, you can use it too), and I was able to detect my VHF tag from a distance of about 1.2 kilometers and 800 meters for the VHF tag I received from @Rob_Appleby  . This is just a rough test.

If you need a receiver that can operate across a wide range of frequencies, I think the RTL-SDR would be a good option as well.

This may not be the best method, but it works just fine. Thank you, and if you have any questions, don’t hesitate to ask me.