This is a follow-up to my last post, “Cattails.”
First I need to tell you a little about a certain salamander, the rough-skinned newt, since they feature prominently in this post. Rough-skinned newts can be about eight inches long; they have a rich, reddish brown back and orange undersides – very distinctive. They are at home both on land and in the water.
There are a variety of newts in the world, and a handful in North America. I don’t know if other newts are poisonous, but the rough-skinned newt certainly is. According to Wikipedia the skin of one rough-skinned newt contains enough toxin in its skin to kill 30 adult humans! … that is if you carefully divided the toxin into 30 equal portions. I can’t vouch that they are really that poisonous, but I have heard a reliable account of a researcher who just touched the tip of his tongue to a newt and was temporarily so paralyzed that he probably would have drowned if he had been by himself. It gives me the willies to think how often I’ve seen children playing with newts. They are so easy to catch.
Both Wikipedia and our reptile book says only one animal, the common garter snake, can successfully eat a rough-skinned newt. The garter snake may be temporarily paralyzed but is able to take advantage of this rather abundant food source.
So now you know a little about rough-skinned newts. Those who have been reading my blog for very long quickly learn we like to watch, to observe, to learn something new. Every so often we have the added pleasure of seeing something really unusual … or, perhaps, never before seen. Our world’s fund of knowledge about natural history is still in its early stages. We know a lot, but there is a lot more to learn.
About ten years ago we spent nine days photographing a great blue heron catching lots of salamanders. Since then we’ve taken a particular interest in newts and salamanders as food. Each day the great blue flew in and fed on salamanders. We knew rough-skinned newts were common in the lagoon and hoped to see the heron grab one. He never did. He must have read the right books. He mostly caught small salamanders, probably northwestern salamanders. Occasionally he caught a much larger salamander – probably a Pacific giant. The big salamander made quite a lump going down. Each time the crane swallowed a Pacific giant, he drank a little water and then ruffled every feather in his body, as if to say, “YUCK” …. “Double YUCK!”
Otter eating a salamander, probably a northwestern salamander.
Our next intriguing salamander sighting was Oct 27, 2007, at Lake in the Woods (see my last post “Cattails.” A family of otter came out into the small lake and caught a lot of prey. Often the otter were too far away to see if they were catching fish or salamanders; but at least some of the time, they were catching salamanders. Some of these salamanders seemed to have the tell-tale orange color characteristic of rough-skinned newts. But we didn’t feel we could tell for sure. We returned the next day and so did the otter, but still our photos weren’t good enough. On our third try the otter didn’t return.
So we’ve been keeping a sharp eye open, hoping to verify otter eat rough-skinned newts. Earlier this month we had another opportunity, once again at Lake in the Woods. We were quietly eating lunch when a lone, rather large, otter swam into the pond. Dale immediately set up our big 500mm lens and waited. This time we felt the photos were good enough to send off to our reptile expert, Alan St. John. He immediately forwarded the images to Professor Edmund Broadie who has studied the rough-skinned newt’s toxins. Both were very interested in our sighting.
First they made sure we think the otter were actually eating the newts, and not just mouthing them. We think they were, but can’t be totally positive. We got to watch a lot of catches and are familiar with how an otter chews its prey. It definitely looked like feeding. Prof. Boadie also told us our sighting is possible. At this elevation, i.e. 3000 feet, the newts are known to have less toxin than at lower elevations. Professor Broadie is hoping to come to Oregon next spring and measure the level of toxins in these newts. … that is how interested he is in our sighting!
The day I painted the cattails, we had returned to Lake in the Woods hoping to see the otter again, but no such luck. We’ll be keeping our eyes open when we are there, hoping for some even better photographs. Meanwhile, it delights me that we have seen something truly unusual.