Tuesday

Pickling a Snake

I have been doing a lot of work with the herpetology collections of late. The past two weeks have seen me pickling and tagging all kinds of neat critters including a  Mojave Zebra-tailed Lizard (Callisaurus draconoides rhodstictus), the first in our collection, and a Striped Racer (Coluber lateralis lateralis) with 10 eggs inside her. For your enjoyment here are the steps to prepare a snake for a herpetology wet collection- in this case another Striped Racer.

1. Freeze the critter- we do this to kill parasites and because we cannot always pickle them right away. Keep in mind that the longer they sit the freezer the more likely they are to become freezer mummies. This guy was only in the freezer for 5 days, but I did a few that were pushing it at 8 years.
2. Thaw the snake and massage it to remove and bends. Basically, be a chiropractor; pull, twist, and rub all the kinks out of its spine so it can be recoiled into a nice shape in the jar.

3. Sew its tags in. Because this is a snake the tags are sewn on rather than tied around a limb. The needle is inserted under the vertebral column- on the ventral side- then a square knot is tied on the dorsal side of the snake. Remember to use good quality cotton thread, a non-dissolving paper, and no-run ink. Our herps get a tag with their catalog and another with all their collection information. 

4. Pickle it! This entails injecting the body with formalin (10% buffered formaldehyde). For a snake this size I inject formalin every 1.5 inches beginning a few inches below the anus. As this snake is male a hemipenis had to be inverted via injecting fluid. NOTE! Inject lots of formalin around the gall bladder lest it rot and turn your snake green and gooey.

5. Massage the formalin around in the body cavity.
6. Coil the snake in the jar so the tags face the outside of the jar. Make sure the snake is not twisted around, is as close to the sides of the jar as possible, and its mouth is closed.

7. Fill the jar with more formalin. If the snake is floating there are air bubbles in it. If this happens massage them out, inject more formalin, and try again (this snake is under a Gopher Snake [Pituophis catenifer catenifer] to save space)
8. Admire your beautiful snake while you wait a week or so for the formalin to set.
9. After a week transfer the snake to a bucket of water. If the snake has no abdominal openings make small incisions on the belly to allow formalin out and water in. Allow to sit in water for a week changing the water every day or so.

10. Place snake into a clean jar and fill with low concentration ethanol.
11. After one week transfer the snake to a final jar, fill with clean 70% ethanol and place into the collections.
Here are some Tiger Salamander larvae (Ambystoma californiense) ready for shelving.

New Birds

I went birding a few times this past week and added a number of new birds to my life list. The first were the Lesser Scaup (Aythya affinis) and Ring-necked Duck (Aythya collaris). I saw both of these in a small pond in a shopping center in Austin, TX. Later that day I saw an Eastern Phoebe (Sayornis phoebe). This weekend while on a family birding outing we saw an Allen's Hummingbird (Selasphorus sasin). This little guy was a very good model showing us his front, back, and gorget for at least 30 seconds a piece. 

The Lesser Scaup is found throughout North America  and migrates to Meso-America in the winter. It's a fairly small duck with adults averaging 17 inches in length. It inhabits freshwater eating molluscs, crustaceans, insects, and aquatic plants. The IUCN currently lists it as Least Concern though sine the 1980's there has been a sharp decline in number from 7 million to 3 million birds. The causes for this decline are as yet unknown but could lead to a change in its listing status.

The Ring-necked Duck is found in wooded ponds in the US and Canada and is a rare but common vagrant to Europe. The juveniles depend on insects and other invertebrates as well as water plants for food while the adults are eat mostly vegetation. Their name comes from the two rings around their bill, one at the base and the other near the tip. The IUCN lists it as Least Concern.

Eastern Phoebes are found in woodland, scrub land, and farmland throughout much of North America. Like all members of the tyrant flycatcher family these birds are insectivorous though they will eat berries in cooler weather. They often nest on man-made objects such as bridges. The IUCN lists them as Least Concern.

Allen's Hummingbirds have a very restricted range being found only along the California coast from Santa Barbara northward and in a very small population in Oregon. They are nectivorous and insectivorous. Like all hummingbirds they have extremely high metabolisms and must feed frequently. Hybrids with Anna's Hummingbirds (Calypte anna) have been known to occur. The IUCN lists this species as Least Concern.

Penguin Dissection

Warning, graphic biological images ahead!
This past week I had the opportunity to assist with the dissection of a Chinstrap Penguin (Pygoscelis antarcticus) to help some people out with their Ph.D work. The penguin was given to them after undergoing a necropsy by a zoo/aquarium vet. As such its internal organs had been removed therefore turning it into a study skin was not possible as the vet had done a number on its chest. This little critter died of old age and has since been put to good use in 4 Ph.D projects and one side project. Its eye, feathers, tongue and windpipe, and hind limbs are all being utilized as part of people's theses. 
The tendons of the foot; this is the back of the ankle.
The projections on the tongue and palate allow the bird to grasp its slippery prey.
These are some well insulated birds. In addition to having the most dense feathers of any bird group penguins also have a layer of fat to keep them warm.

Some facts about Chinstrap Penguins.  They, like all penguins, are found in the Southern Hemisphere. They are fantastic swimmers and catch krill, shrimp, and fish as food. There are an estimated 12-13 million Chinstraps, as such the IUCN lists them as Least Concern. In the wild they live to about 12 years and in captivity around 20. They are known to be an aggressive species. Penguin feathers have a different melanosome (pigment containing organelle) in them than those found in other bird groups.