Friday, September 28, 2007

Necrophila americana

Last fall when my dad butchered a sheep, he dropped the pelt on top of the head, which he had left under a tree, and he forgot about it. A week later when he was passing by it, he grabbed the pelt, and under it was a perfectly clean sheep skull. Maggots could definitely not work that fast, so I asked a biology teacher who attends our church. He said it sounded like the work of a carrion beetle. After that, any time we came across a dead animal, we would put wool on top (to avoid predators or the domestic dogs finding out) and check on it a week later. I had never seen the creatures doing their work, since whenever I would check on the skeleton, the process was done.

Earlier today I was photographing a squirrel. After I was done, I turned around, walked two steps, and nearly stepped on another squirrel, except it was dead. Covering its opened wounds was the unmistakable American Carrion Beetle (Necrophila americana). These beetles are some of the best beetles for nature. As you can tell by the name, they eat carrion (dead animals). When an animal dies in warm weather, it immediately starts decomposing, releasing a stench that of course attracts flies (specifically, the big shiny green ones, Green Bottle Fly) and all sorts of Carrion and Burying Beetles. Judging by the disturbing view that I saw, they had just started on the squirrel, and they always start in the open areas.

I'm not sure entirely how long it takes for them to take care of certain sized animals. For each of the carcases that I have put out there for them, I would just go out a week later and find a perfect skull that was in need of dusting. For this dead squirrel that I found, I forgot to check on the carcass the next day, so I went out there two days after finding the body, to not find anything. If I had to guess, they finished their work quickly and cleanly, and some wild carnivore took the bones. I'm hoping that one day when I find them again, I can collect them and put them to work on a body in a certain protected area, and I can check on it daily to check out their work.

Carrion and Burying Beetles also help with the fly population. Obviously these beetles can just keep eating and eating. So the maggots that the flies leave on the bodies are competition. When the flies first lay the eggs (if you ever see sawdust looking stuff on something, they're fly eggs), the Carrion Beetles completely ignore them. Then when the maggots hatch and start devouring the meat, the Carrion Beetles start going for them too. I guess flies will just have to lay their eggs on things that Carrion Beetles can't get to.

This was all the information that I could gather on Carrion Beetles. However, if you find more information, please let me know, since I'm sure there's much more to discover!

So if you find a perfectly clean skeleton or skull, I'm sure you have the Carrion Beetles to thank for that!

Tuesday, September 25, 2007

Nematomorpha

videoWhen my friend and I were traveling along the creek, we admired all the frogs when she gasped, "What is that?" I looked to where she was pointing to see a a wire looking thing moving around in the shallow waters. We immediately grabbed it and brought it to the house and put it in a clear container full of pond water to get this video. It was probably around five inches long and very wiry. We let it go and immediately start researching. We found what we had discovered was the Nematomorpha (from the Greek nema, "thread," and morphe, "shape") . Commonly known as Horsehair worm or gordian worm.

One look at the worm, and you think it's a parasite. It is. But it's completely harmless to humans and pets. Instead, it's a parasite of insects which makes them helpful for the insect population. The larvae lives in the insects, and when juveniles, they come out and live in the nearest water source. These worms are commonly found in puddles, streams, ponds, water troughs, and even backyard swimming pools. Every so often, they're found in toilets freaking people into thinking they are a human parasite.

Although the one that I had found was only around five inches long, these millimeter thick parasites reach up to one meter long. The reason for their common name "Horsehair Worm" is the rumor that a horse's hair would fall into a water trough and come to life. Their other name "Gordian Worm" came from the way they would bring themselves into a tight knot (the one that I saw did this when I took it out of the water) that specifically looked like a knot that Gordius, king of Phrygia around 330 B.C. used. As the myth goes, Gordius used this knot to bind a chariot to a pole. He declared that whoever could undo the knot would become ruler of Asia. This knot is commonly known as the "Gordian Knot".

Horsehair worms reproduce in spring, early summer, or autumn. Eggs, often numbering in millions, are laid in long strings similar to gelatin. When laid in the water, the incubation may range between 15 and 80 days, depending on water temperature. The mode of development of the worms after hatching is much to question. Some experts suggest that the larvae encyst on vegetation along the water's edge after hatching. Eventually, some of this vegetation is eaten by the insects in which the larvae will feed upon until juvenile. When it emerges, it usually kills the insect (as the way of helping the insect population).

So these creepy tape-worm looking parasites, are really friends to humans. Who would've guessed that these simple creatures are of such interest?

Tuesday, September 4, 2007

Pond Sharks

The picture here is of a Common Snapping Turtle (Chelydra serpentina). It was taken almost two months ago when we saw our little pond shark decide to take a sun bath (to avoid scaring it, I did a belly-crawl for a hundred feet). This was the only time we saw the animal on land.

Hearing my mom screaming something outside the door to my dad, I knew it wasn't good. I ran up the stairs to see Mom pointing vigorously out the back door at something. "Something's got the duck!" she screamed. I jumped out the back door and ran to where my dad was just standing by the edge of the pond staring and looking furious. One of our 7 week old ducklings was floating upside down with the flesh stripped from it's neck and a turtle head the size of goose egg disappearing in a mud cloud. "It's that snapper," he mumbled. "Where's your fish net?" Although my fishing net probably couldn't catch something that was 15 pounds and cement jaws, it was worth a shot. I got the net and came back. My dad was still staring at the mass of algae not far from shore. We waited with the net for about twenty minutes. Twice, the same head appeared a couple inches from the surface and bobbed there for a few seconds to check it out. But after that second time, it probably figured that it couldn't finish its duck.

That's just snappers for you. And we wondered where all of our ducklings that our ducks hatched went. Probably just more victims of our pond shark. It's just nature, but it would be nice if they could just go for all of the fish in the pond as opposed to our gorgeous ducks. There's no saying how old the turtle is since all of the resources that I'm finding are saying different things. Some are saying that wild snappers only live to 30 and others are talking around 100. Agreeing with the latter, I'd have to say that this turtle is close to twenty years old.

The pictures here are of a baby snapping turtles that are probably around six months old (they hatch in fall). I found this one in a puddle about ten feet away from the creek. I brought it to the house and weighed, measured, and photographed it. The funny thing is that I found another baby snapper two days later taking a swim down the creek. I knew it wasn't the same one though because of its measurements and weights. These two measured 1' in length and width and both around half an ounce. These were definitely not hatchlings since when they first come out of the shell, they're only about the size of a quarter. They had to have been from the same nest, considering they were only 1/8 of an ounce or an inch apart in size. And since we live up north where it's cold, they probably stayed in the nest for the winter, and had just come out for spring. They also looked the exact same, so they had to have been the same sex. I'm not sure how to tell the difference in sexes at that age, but female and male's plastron (under-shell, as pictured above) are slightly different along with their tail as shown in this diagram from Ehponline (scroll down, till you see an illustration with an upside down turtle). You see, just like crocodiles and alligators, the sex determination of the animal is based upon the temperature when they were incubated. Males will hatch if incubated between 22 and 28°C, and females are produced if outside that range of temperature. Considering the crazy weather we've had the past year, it wouldn't surprise me if these were females.

Unfortunately, there's a chance that the turtles that I have caught are already dead. It's very unfortunate to be a turtle. The chance of them surviving to adulthood is very little. The female will lay around 50 eggs, but there's a good chance that a raccoon, coyote, fox, or any other carnivore will dig up the nest before they even have the chance to hatch. Even after hatching, they have to survive without being eaten by large fish, herons, minks, or raccoons. It doesn't really help that it can't curl up in its shell as tight as most turtles can. As you can see, the baby turtle here is trying its best but not succeeding that well.

Well, unless we want all of our ducklings to disappear, we'll have to figure out some way to catch those snappers... without harming them. We still want them in our area, just not in our pond eating our ducks. (We started with 14, now we're down to 8.) Then again, it wouldn't surprise us if the coyotes are helping with those numbers. So if there is a way of catching them, we'll just relocate them to the creek where there are plenty of other snapper friends.

Monday, September 3, 2007

Canis latran


The coyote (Canis latran) is a shy and very common predator. We've only seen them a couple times, and of course we've heard them at night (Canis latran is Latin for barking dog). We've never had trouble with them. They're like wolves and dogs, so of course I've had an interest in them. My liking for them now is plummeting by the day.

It seemed to have changed two weeks ago when we had a solid weekend of rain. The pastures had flooded, the creek had turned into a river, and the river had spread into the sheep pasture. Ophelia's ewe-lamb (the black with white spots on her face) had disappeared. Considering the newly formed river in the sheep pasture, we had all assumed that she had gotten caught in the river and had been washed away. It still didn't make sense though. The rain had stopped and the pastures had gone dry again. Then Minerva's ram-lamb (the black and white spotted) disappeared. This time we knew it wasn't the flood. The only other thing that could've done this was a coyote.

So we examined the pastures and found huge gaps in the electric fence due to holes in the ground. We hung extra electric wire on the fence to fill the gaps. Our guard dog that had been with the goats, we put in the sheep pasture. No lambs were taken for two whole days. Then we saw the dog trotting down the road. Not knowing how he got out, we stuck him in with the goats again. The next morning, we went outside and discovered that two twin rams (the white ones) had gone missing. After fixing the fence so that the guard dog couldn't get out, we put him back in there last night. This morning, we went out there to discover that Majik's ram-lamb (the heavily spotted white, gray, and black) had gone missing.

The odd thing with all of these attacks is that there has never been one speck of blood. Usually when they carry off lambs or kids (baby goats) they leave a trail of blood. But in books and websites, they talk of larger breeds of sheep, and we have Shetland Sheep which is a small sheep (running 50-100 pounds). The lambs can't be more than five to ten pounds. There's a good chance that they just grab hold of the neck of the lamb and take off. Scientists say that coyotes highly respect electric fences. When an animal gets shocked by a fence, they don't try to go between the wires or over the fence because they don't know when the voltage ends. However, local homesteaders are saying that more coyotes are learning that they can simply jump through the fence and even touch the wire, but not get shocked. To get shocked by an electric fence, you have to be grounded. So obviously this coyote (or coyotes, considering we lost two at once) has figured out the simple world of the electric fence.

But why are these coyotes going after our lambs? What's wrong with all of the rodents and rabbits? Are there enough rodents and rabbits? The population of coyotes is steadily increasing for many reasons. The main reason is when female coyotes are stressed, the have more babies, earlier in their life, and more often, according to the December 2004 issue of Ranger Rick.

Another reason is Tyzzer's disease. Tyzzer's is an untreatable disease that is transferred from animal to animal from fecal to mouth contact. It started in laboratory rodents and then it was discovered in Iowa muskrats. It's not rare for them to be found in all laboratory animals worldwide. In many areas, Tyzzer's is making dents in the wild rodent population (muskrats, rabbits, mice, rats, etc.)

Spring comes and rabbits are out and about. We can't go down the road without nearly hitting a rabbit. Usually we'll come across many rabbits. This spring came, and we'd go down the road and we might see a rabbit. We'd go into the woods and every now and then a rabbit would jump out of nowhere and run to the nearest hiding place. But then in May we'd never see rabbits running down the road, or jumping in the path in front of us. Not being a big deal, we just shrugged it off.

We've always had trouble with mice in our milking parlor, but this past spring and summer, not a rodent has bothered us. Our LaMancha goat, Muse, was a bit thinner than normal earlier this summer, so we dewormed her and gave her more grain at milking time. In July, she got diarrhea, so we started give her treatment for Coccidia (a single cell organism that affects animals like a parasite). One morning, I went out there with a milk bucket and when I milked her, she had no milk. Maybe two drops. The previous night, she seemed a bit low, but we just assumed she hadn't gotten enough to drink. I told my mom that she was dry, but she wouldn't believe it. A goat cannot dry up in less than 24 hours. The following evening when I was bringing in the goats, I heard Muse letting out muffled screams from the goat shelter. I ran in there to see that she was having convulsions and was foaming at the mouth while screaming with her two kids standing next to her staring at me as if saying, "Can't you do anything?" I ran to get help and we carried her into the barn, and ten minutes later she died. With such an unexpected death, we brought her to the local vet for an autopsy and a week later, they called and said it was Tyzzer's. They had never heard of it being in a goat. We immediately started researching this mysterious disease. It took a couple days for us to put two and two together, but we finally realized this was why we hadn't had mice in our milking parlor or rabbits running down the road.

So the wild rodents get Tyzzer's and die, and the coyotes have no food. I'm surprised they didn't discover our buffet sooner. The only thing we can come up with is that the flood drove them over here and they discovered that they have five pound meals right in front of them. Our only option is to move the sheep. As soon as they have all of our lambs, they're gonna start going for the adults too. We'll figure out something... and hopefully the rodent population will go up again.