We received the toxicology report on the yearling yesterday, and it was equally as unhelpful as everything else we’ve learned so far. No disease, no toxins, no pesticides. No clues that might point us in the right direction at all.
We have run extended organophosphorous and carbamate compound screens. We have tried the GC/MS and LC/MS screens to see if we could pick up drugs or other possible compounds. All were negative. We tested for the metabolite of bromethalin and for strychnine, both of which were negative. There was no obvious inflammation or necrosis to indicate an infectious etiology. We have exhausted most of our tests. If you can think of anything else you would like to test for, let us know.
But there was a sentence that got me thinking.
We cannot rule out toxic plants that may have been ingested
Toxic plants? Toxic plants? What’s toxic to beavers? Only one plant that I can think of. And it’s been historically called ‘beaver poison’. It’s Cicuta douglasii or water hemlock. It’s the relative of the plant that killed socrates and is so lethal for mammals that wikipedia says
this plant has an enormous impact on animals. It is one of the first plants to come out in springtime, and has a very appealing odor.[3] As little as 0.2%-0.5% body weight for sheep, 0.1% body weight for cattle, 0.5% body weight for horses, and 0.3% body weight for swine can be lethal. Death can occur within fifteen minutes of ingesting this toxin. These characteristics, along with the fact that it grows in moist areas make it a very desirable, yet deadly, plant for grazing animals.
The plant closely resembles the water parsnip, a harmless common flower that I’ve observed over the years in our Alhambra Creek. (In fact when we picked up our original mom she was on the little spit by starbucks surrounded by what I assumed was parsnip. But I also vaguely wondered if it was hemlock, and if she knew she was going to die and sought it out on purpose.)
Water hemlock is NOT harmless. It is the most lethal plant we have in America. The plant is indigenious to North America and common in California streams. So it wouldn’t be unusual for it to be in our stream. Or for a hungry beaver kit to feed opportunistically on this easy sweet smelling plant. I’m sure adults would get more cautious and know to avoid it.
I also thought yesterday about the change in our habitat which has meant less ‘kit friendly’ food sources. (Over the years we have seen kits eat mostly blackberry branches, (easy to reach) which have gotten fewer and far between in the current habitat. Maybe from beaver browsing or deliberate city-laden pesticides or who knows?) The creek bank used to be draped in vines and now it isn’t.
What if our sweet kits turned towards another easy sweet smelling food source?
Here’s the flower, which you’ve all seen because it looks the same as so many others. And here’s the leaves which are uniquely serrated. This plant is lethal to humans to touch. So if you see it do NOT do anything other than let me know. 
It would be a fairly reasonable theory if it showed up in our midst and the kits partook. that could explain what happened and why nothing else has been found. I talked with the pathologist and they’re interested.
The seeds are the most poisonous part, and apparently it goes to seed in late June early July. When happened to be when our kits died.
I guess it makes sense that young might eat it. But harder to explain about junior who should have known better. Still our habitat or the drought could have made it more available than before, and there’s no proof that he died of the same thing as the kits anyway, I guess.We just don’t know.
I’ve spoken with some plant experts to see if we can get this diagnosed for sure. In the mean time I know what I’ll be keeping an eye out for. You too. Look but DON’T TOUCH.
Thereupon Crito nodded to the boy who was standing near. The boy went out and stayed a long time, then came back with the man who was to administer the poison, which he brought with him in a cup ready for use. And when Socrates saw him, he said: “Well, my good man, you know about these things; what must I do?” “Nothing” he replied, “except drink the poison and walk about till your legs feel heavy; then lie down, and the poison will take effect of itself.”
Such was the end, Echecrates, of our friend, who was, as we may say, of all those of his time whom we have known, the best and wisest and most righteous man.
