Sunday, September 23, 2007

Hunchback of Colorado

It’s been a while since wrote about a fish, and I figured out I could search IUCN for all the Actinopterygii, that is, the ray-finned fish. Then found I could order the search by their category. While I found the pretty cool Shovelnose Sturgeon, there wasn’t enough information for me to write about1. The IUCN has recently highlighted the Humphead Parrotfish, which is ugly enough, but since they just highlighted it, I’ll let them talk about it.
Image by John Rinne via FishIndex
The Razorback Sucker (Xyrauchen texanus) is not too distantly related to the Blue Sucker that I wrote about a while ago. While it has a similar habit of eating organic detritus from the bottom of rivers, this one is lives in the Colorado River basin. It’s also larger, reaching lengths up to three feet, making it one of the biggest Suckers in North America. It has a big, sharp hump that gives it its name, which helps it navigate the fast moving rivers it calls home.

These Suckers are comparatively long lived, beginning to spawn at about 4 years old, and can live up to 40. However, despite their longevity, most of the young are dying early. This is mainly attributed to the large number of invasive predator fish that have been introduced into the Colorado River. Fragmented habitat and dams have also negatively affected their numbers. After all this, scientists estimate there are only about 500 adults left in the wild.

There are conservation efforts in place, many of which revolve around hatcheries in Utah and Colorado. The numbers are beginning to increase, and they’re certainly working on removing the invasive fish from the river.

1I’m getting pretty good at determining if I’ve got enough information fairly quickly anymore. A lot of that has to do with the number of photos Google has.

Sunday, September 16, 2007

It's a Bird! It's a Plane! It's a Gliding Mammal!

Image from Colugos.com
Image from Colugos.com
I don’t have any good quips for an introduction this week, but I’d like to let you know that this genus is much creepier in motion. Start this video at 5:31 to see it1.

The Philippine Colugo (Cynocephalus volans) is also known as the Philippine Flying Lemur. I won’t use that term again in this post for two major reasons: a) it doesn’t fly2, and b) it’s not a lemur. It is from the Philippines, so I can keep with that. They fit into the many, many gliding animals that are given the name “flying ___”3. There are only two species of Colugo, both in the genus Cynocephalus, which means “dog-headed,” which seems to be an accurate description. The Order, which is not too distantly related to the primates, is Dermoptera, which means “Skin Wing.” They’re not actually wings, but membranes that extend from the tips of their fingers to the ends of their toes.

Colugos spend their days in tree hollows. In the evenings, they dine on young leaves, which aren’t terribly nutritious (but more so than the older leaves), and run out on an individual tree fairly quickly. This is all right because, since they live in the Philippine jungles, fresh, new leaves are just a short glide (or not, they can glide for about 100 meters) away. Their hands and feet end in sharp claws for grasping onto trees, which is helpful if you never touch the ground in your life.

Young Colugos are born early and undeveloped, much like a marsupial. However, the mother lacks a pouch, so, instead, she folds up her tail and carries the young there until it can fend for itself. This means a mother can only have one, or at most, two, every few years.

Of course, a low birth rate means slow recovery from any threats that these animals face. The biggest threat, no surprise, is habitat loss. They don’t have a very large range, and the area is being developed fairly rapidly. Since they are wild herbivores, and like a good rubber tree leaf as much as anyone (probably more), plantation owners frequently regard them as pests, and deal with them accordingly. Habitat fragmentation is also causing a problem, as individual populations get cut off from one another, leading to less genetic diversity.

1If you’re interested in African Hunting Dogs, Indian Tigers, or the Amur Leopard, feel free to watch the rest of it.
2The difference between flying and gliding is simply the fact that fliers are able to increase velocity in midair, while gliders just fall really slowly.
3 Squirrels, snakes, “dragons”, squids, frogs, fish, and geckos, to name a few.

Tuesday, September 11, 2007

Calling On - Weta

I was going to write about the Hairy Marron, the fuzzy crayfish from Australia, but I couldn’t find enough information about it, least of all why it’s hairy. So, this week’s post is about the other arthropod I mentioned in the footnote of the Hunter Slug post.


Image by Gerald Cubitt via ARKive


Wetas are cricket-like insects native to New Zealand and frequent (possibly even preferred) prey of Tuataras. The Poor Knights Weta (Deinacrida fallai) belonging to the genus of Giant Wetas1, is amongst the largest insects in the world. They approach 8 inches in size when mature. As they are flightless, being light is not a concern, and thus, when laden with eggs, they can be heavier than sparrows.

The Poor Knights Islands are two small, uninhabited islands off the coast of New Zealand, apparently named for their resemblance to French Toast. Personally, I don’t see it. The islands are a nature reserve, and the 800 meters around the islands are protected as a marine reserve, and apparently a great diving spot2. The trees on these islands are where these Weta live, moving to the ground to lay eggs. They may also live on another nearby island, as a Giant Weta fecal pellet was found there. Please, don’t ask me how they determined that it was from Giant Weta.

Poor Knights Wetas are nocturnal and herbivorous, and their main defenses lie in being gigantic and spiky. An adult female can lay 200 to 300 eggs per clutch, which appears to be a one-time deal in a two-year lifespan. They’re listed as Vulnerable by the IUCN, even though they don’t seem to be declining. What they’re really worried about is the small size of their distribution, contained to small islands. They're also worried about the risk of a simple introduction of a non-native predator and its effects. The Wellington Zoo in New Zealand has a breeding program, both as a safeguard against extinction, and for public education.

1The genus name, according to Wikipedia, means “Terrible Grasshopper”.
2At least, according to the Tourism Department

Sunday, September 02, 2007

And the Vultures Circle

Well, it’s high time for another bird post, and I have just the animal for it. It was mentioned in the Waldrapp Ibis post as another bird seen at the Cleveland Zoo, and I even linked to a picture of it. This picture, in fact:

Image by Me
Image by me

The Cinereous Vulture (Aegypius monachus) is also known as the Monk Vulture or Eurasian Black Vulture. They’re found in mountainous areas all the way from Spain to the Himalayas. Due to their high lifestyle, they’ve developed a special hemoglobin molecule to help take in oxygen at altitudes where we would be sucking on air tanks. This vulture has even been spotted 23,000 feet up Mount Everest; that’s about 80 percent up to the summit. The tree line would have been about 8,600 feet down.

With an 8-foot wingspan, the Cinereous Vulture is the world’s largest “falconiforme,” the group that contains the true birds of prey. Finding this led to an interesting discovery: Old World vultures are unrelated to the New World vultures; all similarities between the two are a result of convergent evolution. While the Old World vultures evolved from hawk- and eagle-like birds, New World vultures—such as our beloved turkey vulture, or the largest flying bird, the Andean Condor—evolved into a similar niche from storks. This confusion on relationships even led to the common name I’ve been calling Aegypius monachus. It needed to be distinguishable from the American Black Vulture, now considered unrelated, so it was given a name meaning “ashy colored,” thus, “Cinereous.”

While the Cinereous Vulture is only listed as Near Threatened according to the IUCN, Europe1 classifies it as Vulnerable. The population decline is frequently attributed to poisoned meat set out to kill potential livestock predators, and a general lack of carcasses lying around due to quicker removal of dead cows, which were a historical food source.

Thankfully, European conservationalists have kicked into gear, so the Cinereous Vulture may never have to see the Threatened category on the IUCN list. Breeding programs have been set up in France, Spain, and heck, there’s even a breeding program at the Cleveland Zoo. Due to good management practices, their numbers are increasing rapidly in Greece. Actual direct hunting of the Cinereous Vulture has pretty much stopped because of outreach programs to the public.

1I didn’t even realize there was a list for all of Europe! Though, I can’t seem to find the list itself.