Hungry snakes – rough green eats a spider

Rough Green Snake

Following up on the recent post showing a video of a copperhead eating a cicada, here is a cool video from Joe Letsche showing a rough green snake eating a spider. Invertebrates are quite appetizing for some snakes!

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Fascinating video: copperhead eating molting cicada

Here is a fascinating video by Kenneth Gisi of a copperhead (Agkistrodon contortrix) eating a molting cicada. Kenneth noticed this just as the snake started to eat the cicada, and his video goes all the way to when it has completely swallowed the cicada. Well worth watching over and over!

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How to tell apart male and female spotted salamanders (and other Ambystoma)

Spotted Salamander in Pond

So you are outside on a rainy, cold day in late winter, walking around your favorite vernal pool, and you find an Ambystoma salamander. These are the large North American salamanders that often (but not always!) live on land as adults, but migrate to breeding ponds to mate and lay eggs. Once you’ve got one of these salamanders in your had during the breeding season, how can you tell if it is a male or a female?

In an earlier post, I showed how to tell apart male and female wood frogs during the breeding season based on the shape of the front limbs. That method won’t work for spotted salamanders or other Ambystoma; instead you’ve got to look at the cloaca.

The cloaca is the orifice just past the hindlimbs in salamanders. The cloaca serves two main functions: excretion and reproduction. During the breeding season, the cloaca of male Ambystoma are enlarged, while the cloaca of females remain smaller. If you can pick up your spotted salamander and flip it over, you can easily tell its sex. Unfortunately this approach won’t work if you find an Ambystoma during the summer, because the males do not have enlarge cloaca outside of the breeding season.

Salamander Anatomy Cloaca

Female Spotted Salamander Cloaca

Male Spotted Salamander Cloaca

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Flute, Horn, and Treefrog

I was recently contacted by Spencer Arias about using one of my gray treefrog recordings in a piece of music he had composed. Spencer is a member of The New Collaborative, a group of composers who write music based on prompts from their audience submitted through facebook or twitter. The piece Spencer wrote was in response to a prompt of “amphibians.” The use of prompts to give direction for music is a cool idea, and the final piece is fun and interesting to listen to. After listening to it a few times, I was struck by the serendipitous way in which a recording I made one warm summer night in a Michigan pond ended up in a piece of music recorded in New York City and broadcast around the world on youtube.

Composition by Spencer Arias of the New Collaborative:

Video of a calling Gray Treefrog in a Michigan wetland:

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An overdeveloped drive to mate?

Wading around wetlands during the frenzy of amphibian breeding aggregations can reveal fascinating sights and sounds. Male frogs have a wide range of strategies for getting the girl. They might attract a female with song, or lurk quietly trying to sneak in a mating. For some of the male frogs, this will be the only opportunity they have to mate in their entire lives. Consequently, they can get a little overzealous, and errors are made. Males will briefly grab onto other males, but then let go when they hear a specialized “release call” that informs them of their mistake. However, there are some situations where the strong drive to mate combines with the lack of an encounter call with a surprising or even grotesque results.

One such unpleasant outcome is when a male frog amplexes a deceased female. The photo below shows a male wood frog found amplexing a dead female. By the look of it, the female was probably dead for a day or more. Who knows how long the male hung on for!

Sometimes the mix-up is less disgusting, but still interesting. Male frogs will sometimes try to mate with other species of frog, or salamanders. These other species can’t produce the appropriate release call, and so the males just keep hanging on. An example of this is the photo below of a pacific chorus frog trying to mate with a California Newt. I spent six years observing pacific chorus frog breeding aggregations, and it is worth noting that I only saw this frog-on-newt mating a handful of nights. Those nights were always the rainiest nights with the highest densities of frogs. I never saw this behavior cause obvious harm to the newts. However, there may be situations where this can be very bad for the salamander.

Perhaps the most unusual cases are when these two errors – dead animal and wrong species – are combined. I have not yet seen this myself. However, I came across a fascinating example of this on the photo-sharing site flickr. Miha Krofel’s photo below shows a male common toad trying to mate with a dead pike! Click on the photo to go to Miha’s photo stream.

mismatch mating - toad and dead spike

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