Dear Melissa: I have briefly used glue traps in equatorial Africa and Southeast Asia to catch small reptiles. I won’t use it again for several reasons: it mostly catches animals you don’t want; it damages geckos because of their fragile skin; and is definitely very painful for many animals. In some localities in Gabon we got far better results with pitfall traps and active search than with glue traps that were put a few hundred meters away in ecologically similar localities. I think it would be good to explain what kind of study you want to do, in order to allow RG colleagues to rather suggest you alternatives to glue traps. I got a lot of Lycodon by active search at night, and many Scolopendra in my pitfall traps. Predicting where Lycodon will pass to put glue traps in these places might be quite difficult as well.

Hi Melissa. Scolopendra species have a tendency to disintegrate when you try to remove them from the glue traps, and as Olivier mentions above, there can be very real damage to reptiles. I also agree with his statement that non-target species getting caught is a huge problem. Pitfall traps (esp. ones baited with small pieces of meat or fish) are great for catching Scolopendra sp., but one of the problems I had with this method was that the larger ones would eat the smaller ones trapped in there overnight. For the snake: active searches are the way to go for sure!

Hi to you both thank you for your very informative answers.

Olivier, thank you for your response, a bit more about my study: I aim to look at abundance and density of these two species in a forest, as well as their preferred microhabitats and forest stratum. (Additionally I will be collecting specimens of both species to get gut contents to look for predation on a native gecko, although this will be during a different period of time). I will also be trialling bait palatability tests in the lab and developing an effecting trapping method for both species with the view to develop future control strategies and or eradication on the island (Christmas Island, Indian Ocean). Both of these methods however require a trapping method that works well, and does not harm the animal, so from what I hear, using sticky traps may not be a great option.

Aleksandra, thank you for that useful info, I agree that Scolopendra may be too delicate to use on glue traps. I do plan to use pitfall traps as one of my trapping methods, however the issue with baiting them where I am, is that the crab population on the island is so high, they often get filled up with crabs instead of target species. I have considered developing some kind of arboreal pitfall trap as both of these species are partly arboreal, however there is not much literature on this method. (If you know of any alternatives, please let me know).

It sounds like for the snakes atleast, active searches are the way to go. Active (destructive) searching during the day by turning over logs and bark and rocks may work well for scolopendra but I am unsure if this would heavily impact the repeatability of this method to get an idea of abundance. Have either of you tried this?

Thank you.

Olivier, I just had a look at your publications, I see that you have worked on Cyrtodactylus geckos before? The native gecko that remains on the island is the endangered Cyrtodactylus sadleiri. I am also going to be working on this species directly, looking at abundance, density and spatial home range, to try and work out the reason for their continued existence when all other native reptiles have declined. Perhaps you have some insight into work on similar species? My issue will be with the mark and recapture of them, as they are arboreal and nocturnal. Perhaps you used some methods like this with your own work?

Dear Melissa - I am indeed working on Cyrtodactylus systematics and distribution, and have co-described two dozens of species so far, many of them with an extremely restricted distribution, especially the cave-dwelling ones. I am happy to send you the few available papers on Cyrts ecology that can help you for your work - let's continue this discussion through e-mail; pls write to my Yahoo address.

Hi Melissa, I had the same issue with crabs in pitfall traps and got around this by using a bucket with a well fitting lid and having very narrow entrance slits at ground level. Scolopendra sp. can get through the smallest of gaps and this method worked for me while keeping the crabs out. I have never tried arboreal pitfall traps so can't really advise on that. I would say however, that in terms of detection rates, you are more likely to find Scolopendra on the ground than in trees. They do climb, but I always had better luck looking for them on the ground. Active searches for centipedes (turning logs etc. as you mention) can be a useful method for assessing abundance as long as you time each search and try to be consistent about looking under logs and through leaf litter for them.

I think you may have already decided against using glue-boards for snakes, but I'll add that I've heard of snakes losing scales when struggling to get free from them. I don't think I would use them if I didn't want the snakes harmed. Also, as someone else mentioned, you will catch a lot of non-target species. If you do decide to use them for any snakes you plan to keep for post-mortem analysis (if any), you may want to check them frequently to release any non-target species before much harm is done.

Thank you all for your answers. My apologies for the delayed response I have been out in the field for the last couple of weeks.

Olivier, I will write you an email to your Yahoo address about Cyrtodactylus studies as soon as I can.

Aleksandra, I see you were an author in the paper that looked at Scolopendridae centipedes in Mauritius and Rodrigues. Firstly can I just say that's a great paper, I read it ages ago as I myself worked in Mauritius on the reptile team with Nik Cole, and it has provided me with a lot of background info for the Scolopendra biology for my PhD. The idea of using ground slits in the pitfall buckets is a BRILLIANT idea, did you use this method in Mauritius? I think this will work really well at keeping land crabs at bay. I have actually discussed the idea with the park rangers on my field site (who have been using pitfalls on the island for years), and they think it will work really well. Do you have some papers that describe this method in more detail? If so I would love for you to send me a link to them please. If not perhaps I can send you an email and we can discuss the method further?

Jonathan, thank you for the advice, yes I think i might avoid using the sticky traps to catch the reptiles, as the bi-catch on the endangered species in my study site would be a large problem. If i do use them it will be to catch invasive snakes which will then be kept for post-mortem analysis, and I will be sure to monitor them closely.

Thanks again to you all, Aleksandra I look froward to hearing your response.

Cheers.