September Sampling

Well its been a while since I posted some pictures, so here you go.

This lamprey lost its tail a little while ago and it is slowly growing back. You can see the tip is just a little too small for this animal. He has been marked so I have been able to see its tail grow back slowly.

These two pictures are of the same animal. This is a mayfly (Ephemeroptera), and a burrowing species probably Ephemeridae: Ephemera sp. If you look closely you will see two horns at the front of the head, and if you could have held the animal you would have seen its huge Pop-eye arms. Both of these pieces of its anatomy help it dig. And dig it did, when I released it.

Although it is September already we have not gotten much rain lately. As a result all of these rocks should be covered by water at this time of year, but remain exposed. The lampreys are also quietly waiting for water levels to come up so they can move on to greener pastures.

A shot of the water as it passes over the stream bed.

Its that time of the year, when big ammocoetes become juvenile lamprey and head out to the sea. The silvery lamprey are the bottom are now true juveniles. If they survive the trek to the ocean they will begin their lives their, feeding on other fishes.

Here is a close up of the juveniles (sometimes called transformers or macrophthalmia). One of them was tagged last time, but its body consumed the tag. So it was hard to tell which tag it had. Thankfully, it is a transformer which meant it could only be one animal I saw last time.

A downstream view of the stream, ona rock bar that has been building up slowly all summer.

A picture of the most productive ammocoete area in my study.

Here are a series of pictures of the same animal. It looks like a leaf, but its not a leaf, its a dragonfly. This is Hagenius sp., the common name is dragonhunter (link). This species is a large predatory adult animal that actually actively hunts and consumes other dragonflies. Even though the larvae (pictured here) looks a little weird the adult is a normal looking dragonfly.