Sunday, August 31, 2008

I head south

I leave today for Venezuela where I will be until December. The last-minute crush of preparation prevented me from finishing up a couple different projects on here (including the answers for that bone quiz) but they can wait. I'll post if I can but it will not be frequent. Check back in December.

Tuesday, August 26, 2008

Herp of the Day: Rhacodactylus auriculatus

Here's a cool gecko for you - the Gargoyle Gecko. This guy is the genus Rhacodactylus, an group of six awesome species restricted to the island of New Caledonia near Australia. All of the species are fairly large, charismatic, colorful, and consequently popular in captivity. Importation of wild-caught Rhacs stopped a while ago, but they do so well in captivity that captive-breeding has sustained the different species for many years.

Shawn has a big female Gargoyle named Darwin, until recently the only representative of her species that we have available for use in CHS education programs. The Gargoyle is a beefy gecko, with a round body very unlike the flat Hemidactylus featured recently and some other cool geckos coming up soon. Like the other rhacs they are arboreal and have several adaptations for it, including wide feet and a semi-prehensile tail, but this species tends more towards lower shrubbery habitats so they lack the more prominent adaptations of the other Rhac species (big webbed feet and the ability to flatten out while jumping).

The species comes in two distinct morphs - a mottled/banded base and a striped base pattern, and can vary considerable in color from whitish to brown to red to black and white, some with bright orange or red spots and stripes as additional pattern. For the most ridiculously awesome Gargoyles, see the gallery at Rhacos.com.

When Shawn got Darwin as a youngster she was mostly whitish with banding, and twin rows of orange spots down her back:

(next 2 photos by Shawn Billerman)

She has since grown into a portly adult. Her orange spots have all but faded away, but now she can turn a lovely shade of brown with some reddish mixed in. She is also great at demonstrating the variability in color that Gargoyles possess (certainly the best among Rhacs although R. ciliatus can give them a run). She is often nearly pure white while sleeping, darkening up to brown when she's running around at night. Here's a whole gallery of Darwin being Darwin:


(next 2 photos by Shawn Billerman)



If you look closely at some of her head shots, you can see the species' namesake - bony ridges and bumps along the top of their head behind the eyes. They aren't very pronounced in Darwin or in many individuals available in captivity because people tend to breed for color more than awesome head structure, but the bony knobs can be very prominent in wild individuals or some captive-bred individuals. For an example of better head structure, see here.

Darwin is no longer the only Gargoyle in the Cornell herp community. Recently our friend Amanda obtained a lovely male for breeding purposes, so by next year this place will be overrun with little gargoyles. Check out the male's awesome stripes:

(photos by Shawn Billerman)

Sunday, August 24, 2008

I <3 Coal Skinks

I went out this morning with Shawn and Amanda to show my birder friend Ryan a few of the local herp species he hasn't seen. Our main target was Smooth Green Snake (Opheodrys vernalis) but we missed that. It was still a good day though and we got Ryan four reptile lifers. This is also likely my last herping trip in NY for a long time (going to Venezuela in a week, working elsewhere next year), so it was fun to see a few local species before I leave.

Here's a few of my pictures (they aren't that great or comprehensive today because I let the others do the photographing while I kept finding things) and a video:

A toad whose identification is currently under investigation

Brown Snake with cloudy eyes (pre-shedding)

Eastern Garter Snake in mid-shed

Milk Snakes

Finally, the awesome highlight, two (probable yearling) Coal Skinks. These young ones have a brilliant blue tail that the adults lack. Unfortunately one of the juveniles dropped a portion of its tail. I got this video of it wriggling (yes it was silly of me to film it on my knee and not a rock, but you'll have to deal with it):




Our list for the morning:

Green Frog (Rana clamitans) - 1
Pickerel Frog (Rana palustris) - 2
Spring Peeper (Pseudacris crucifer) - 2
Red-spotted Newt (Notophthalmus virescens) - 2
American Toad (Bufo americanus) - 2

Red-bellied Snake (Storeria occipitomaculata) - 2
Brown Snake (Storeria dekayi) - 12
Eastern Garter Snake (Thamnophis sirtalis) - 6
Ring-necked Snake (Diadophis punctatus) - 1
Milk Snake (Lampropeltis triangulum) - 2

Coal Skink (Plestiodon anthracinus) - 2

Friday, August 22, 2008

Oh Me, Oh My, Oh Malaconotids!

*Note: Text and all photos in all Kenya posts are by Shawn Billerman unless otherwise noted.

As I’m sitting here on this 17th day of August, reminiscing about Kenya, I can’t help but write about bush-shrikes. Bush-shrikes are in the family Malaconotidae, and are endemic to sub-saharan Africa. They are part of a large radiation of African and Malagasy core corvoids, being closely related to the Vangas (Family: Vangidae) of Madagascar and the Helmet-shrikes (Family: Prionopidae) and Batises and Wattle-eyes (Family: Platysteiridae). As a group, this radiation is part of the core corvoids, and is sister to an Australian radiation of birds including the Wood Swallows (Family: Artamidae) and the Currowongs (Family: Cracticidae) (see tree below). The Core Corvoid radiation also includes more familiar families such as Laniidae (shrikes), Corvidae (jays and crows), Paradisaeidae (birds-of-paradise), Dicruridae (drongos), and Monarchidae (monarch flycatchers) (Jønsson & Fjeldså 2006; Barker et al. 2004; Fuchs et al. 2004)


Anyway, now for some fun, random anecdotes about this awesome family… While in Kenya earlier this month, I was lucky enough to see eight species of these awesome birds: 2 species of Tchagra, 2 species of Boubou (Laniarius), two species of Malaconotus, in addition to Rosy-patched Bush-shrike (Rhodophoneus cruentus) and Brubru (Nilaus afer). I was able to study Sulphur-breasted Bush-shrike (Malaconotus sulfureopectus), Brown-crowned Tchagra (Tchagra australis), Slate-colored Boubou (Laniarius funebris), and Rosy-patched Bush-shrike for some time, and was astonished at how different they were from each other, especially in song diversity. This isn’t to say I didn’t see similarities between the species… morphologically they are relatively similar, but ecologically, there seems to be a broad range of differences. The Slate-colored Boubou would just walk all around camp, perch atop dead branches, scold passers by, and were very brazen in general. At the complete opposite end of that spectrum, the tchagras I watched were very secretive and skulky, scurrying along the ground, managing to sneak into holes in bushes and under tree roots that I didn’t think were even there.

Rosy-patched Bush-shrike (Rhodophoneus cruentus) (Source)

Brown-crowned Tchagra (Tchagra australis) (Source)

In addition to that, there was a great diversity in the songs of the species. While both Sulphur-breasted Bush-shrike and the Rosy-patched Bush-shrike sang relatively similar, simple whistles, the Rosy-patched Bush-shrike would duet with its mate (sometimes while the two were in the same tree, but more often when its mate was far off). One could stand in the acacia scrubland, watching a Rhodophoneus singing, and in the distance, hear its mate responding. Aside from this, while these two species had relatively simple whistled vocalizations, the Slate-colored Boubous that were abundant around camp had a wide range of complex vocalizations. It actually took me quite a long time to realize that much of the bird song I was hearing around camp was all from the boubous.

Due to the relatively secretive nature of the Malaconotids I saw, I have but one decent picture to share with you of a bold Slate-colored Boubou that was literally foraging at my feet under our mess tent.

Slate-colored Boubou foraging at my feet under the meal table

References:

Barker, F.K., A. Cibois, P. Schikler, J. Feinstein, and J. Cracraft. 2004. Phylogeny and diversification of the largest avian radiation. PNAS. vol 101:30: 11040-11045

Fuchs, J., R.C.K. Bowie, J. Fjeldså, and E. Pasquet. 2004. Phylogenetic relationships of the African bush-shrikes and helmet-shrikes (Passeriformes: Malaconotidae). Molecular Phylogenetics and Evolution. 33: 428-439

Jønsson, K.A., and J. Fjeldså. 2006. A phylogenetic supertree of oscine passerine birds. Zoologica Scripta 35: 149-186.

Thursday, August 21, 2008

Happy Hyrax Rock

*Note: Text and all photos in all Kenya posts are by Shawn Billerman unless otherwise noted.

Around the middle of the trip, our adventures had slowed down, as we buckled down and worked mostly on our projects. However, on one particular afternoon, Irby took the group to Clifford’s Rock, a kopje where Rock Hyraxes lived. And, of course, where there are hyraxes, there is the very distinct chance of seeing a Verreaux’s Eagle (Aquila verreauxii), which feeds almost exclusively on the dumpy, furry creatures. En route to Clifford’s rock, we passed a covey of Vulturine Guineafowl (Acryllium vulturinum). These really are quite bizarre creatures, and definitely more exciting than Helmeted Guineafowl (Numida meleagris).

Vulturine Guineafowl (Acryllium vulturinum) (photo by Jess Marion)

We pulled up to the base of the outcrop, and began ascending. On the way up, we noted some of the fauna that is adapted to these rocky outcrops, like Klipspringer, which look a lot like a large Dik-dik on its tippy-toes. I also noticed a high abundance of Cinnamon-breasted Rock-buntings, and Marico Sunbirds. Also present were African Black-headed Oriole, and my first Red-faced Crombec. We did not see many hyrax at first, but certainly evidence of hyrax presence.

A perfect Hyrax skull found on the ground on the outcrop

For a while, we all just wandered around the top of the kopje, taking in the awesome scenery.

View from the top (or near top) of Clifford's Rock; the class climbing some lower rocks; Neat rock formations

But, our time of relaxation was short lived. Back to work! We all gathered, and we had two of our paper discussions on Clifford’s Rock. One of these discussions was appropriately on hyraxes, and we were under the watchful eye of a pair of Rock Hyraxes as we discussed their meta-population structure. As we were discussing hyrax populations, a Verreaux’s Eagle blitzed by, all the while Wire-tailed Swallows were foraging above our heads.

A pair of Rock Hyrax (Procavia johnstoni) watch as we discuss their metapopulation structure

As Nick pointed out to me in an earlier draft of this post, I talk about talking about Hyraxes, which is silly. So allow me to go into some detail about these bizarre, dirty mammals.

Hyraxes are in their own order, Hyracoidea, and the family Procaviidae. Hyraxes now fall into three genera, Dendrohyrax (tree-hyraxes), Heterohyrax (bush-hyraxe), and Procavia (rock-hyraxes). Hyraxes are part of the Afrotherian radiation, which include Elephants, Dugongs (Manatees), Elephant-shrews, Golden Moles, Tenrics, and the Aardvark. Hyraxes actually form a monophyletic clade with Elephants and Dugongs (Nishihara et al. 2005; Murata et al. 2003).

Now that I've covered the Hyraxes' bizarre evolutionary relationships, allow me, if you will, to go into some of their bizzarrre natural history. Hyraxes feed on graze and browse (Rock hyraxes graze, while Bush hyraxes browse), but do not chew cud. It is due to this inefficient way of extrating nutrients from vegetation that has forced them into marginal niches (source). In addition, hyraxes have poor thermoregulation, and are required to bask in the sun, and huddle for warmth (the necessity to bask leaves them very vulnerable to predators like Verreaux's Eagle). Hyraxes also utilize latrines, which may be hundreds of years old. Latrines may act as scenting areas where all members of a group collect the same scent on fur and feet (Kingdon 1997)

Unlike many mammalian social systems where males disperse and females remain in their natal territory, female Rock Hyrax disperse to neighboring kopjies. However, the number of females that actually disperse is quite small. This leads to lots of inbreeding, where males aquire large harems, often including sisters and daughters (source). (Gerlach and Hoeck 2001)

A final interesting aspect to Rock and Bush hyraxes is that they often live on the same kopjies. In fact, Rock and Bush Hyrax babies are raised in the same nurseries. Although it may seem strange that two different genera will raise each others young, to which there is clearly a cost, the cost of predation is far greater; by sharing duties raising offspring, they can keep better vigilence for predators (Barry and Mundy 2002).

For more pictures, and fun anecdotes about hyraxes, check out this website.

References:

Barry, R.E. and P.J. Mundy. 2002. Seasonal variation in the degree of heterospecifc association of two synoptic hyraxes (Heterohyrax brucei and Procavia capensis) exhibiting synchronus parturition. Behavioral Ecology and Sociobiology. 52:3, pg. 177-181.

Gerlach, G. and H.N. Hoeck. 2001. Islands on the plains: metapopulation dynamics and female biased dispersal in hyraxes (Hyracoidea) in Serengeti National Park. Molecular Ecology. 10:9, pg. 2307-2317

Kingdon, J. 1997. The Kingdon Guide to African Mammals. 296-298. Academic Press, San Diego, CA.

Nishihara, H., Y. Satta, M. Nikaido, J.G.M. Thewissen, M.J. Stanhope, N. Okada. 2005. Molecular Biology and Evolution. 22(9):1823-1833

Tuesday, August 19, 2008

Herp of the Day: Eublepharis macularius

My first, and best, gecko is Sobe the Leopard Gecko. I inherited Sobe from my friend Jenn at the start of my sophomore year. Sobe has a fantastic disposition, being very tame and practically begging for food. I take her on many education programs with the Cornell Herpetological Society.

She's smug because she knows she is the best

So happy chowing mealworms
Investigating the cricket bin

Sobe doing some educating
Here's a sequence of her shedding. Geckos tend to shed in one or several large pieces, eating the shed as they go. Here she gets the shed started on some rocks, then starts pulling off those yummy pieces.


Sobe is a wild-type Leopard Gecko, or about as close to wild-type as you see in the hobby today. She's yellow and has less black mottling than I would expect for a pure wild-type (you can see some first-generation young here). I bred Sobe for one season with my friend Amanda's male Frankie. I forget the exact morph name for Frankie, other than pretty!

Frankie

The unhappy couple

Their coupling gave me several clutches of eggs, from which I hatched three beautiful young, whom I named Audubon, Piha, and Sabine.

A gravid Sobe lets her belly hang free

The eggs are soft and leathery and are laid in clutches of two

The young start off boldly banded and patterned, but as they age the black fades and orange mixes in, showing their father's blood. They grow quite quickly!

Fresh from the egg

One Week

Two weeks - exploring the world

One to two months - less black and more color

3 months - the teenage months

I ended up giving away these young ones before the matured (at around a year old) but watching them grow was a great experience. I miss them and wish I could find out what they look like today. Just a few weeks ago I was forced to finally give up my precious Sobe as well, as I have to give up my gecko collection before my Venezuela work. She was the sweetest gecko and I will dearly miss her. I don't think I could find another Leopard like her.