The Birds and the Sea Lamprey

'Tis the season for love if you are a sea lamprey in the Delaware River. I needed to collect some adults for a project so I went to the Delaware River to do so today. The sea lamprey were out and spawning so I took some pictures and videos while I was collecting.

To find adult lamprey we first looked for these. The picture above is a nest that the adults construct. the small pebbles are at the downstream end and protect the eggs as they develop. Once they are big enough they wash out of the nest and must look for a place to burrow further downstream.

Here is one of the adult lamprey I collected. You can see the eye is already cloudy and the body is starting to wear out. Besides spawning adults are done with their lives. The animals I collected today probably had no more than a couple of days at most. Some of the females would have died tonight.

Same lamprey but with a closeup of my foot to give an idea of scale. These animals were each about 1 pound.

Not a lamprey but a cool sight today. Lots of swallowtail butterflies were puddling in different locations around the stream.

Same butterflies but a slightly different shot.

And finally, a video in case you don't have any lampreys to watch near you.

Video annoyingly tiny? Head on over to youtube, there you can find all my "amazing" lamprey videos.

Youtube channel

The Metropolitan Museum of Art

Though I have received request before to come sampling, I have never received a request from an art museum to provide lampreys. The Met put on an exhibit in which live lampreys were used, and I had the opportunity to collect those animals.

Here is the description of the exhibit and the artist.

And here is the opening ceremonies with the tank and the NY skyline in the background.

Here is someone inspecting the tank. There is a lamprey in the lower right corner.

I did not visit the exhibit myself, these pictures were provided to me from workers at the Met. This is probably the first time most people who visited have ever seen a lamprey, possibly ever heard about them. Any press for lamprey (other than killing them in the Great Lakes) is good press.

Delaware and a little Hudson River

Well I came back from my first longer sampling trip of the summer (first of six). The trip takes me from Syracuse to the Delaware River, to the Hudson River, and then back again to Syracuse. Although I went much further this time than when I traveled to the Genesee River the species was the same in both sites (Sea lamprey, Petromyzon marinus).

The first pictures here will be familiar if you have seen the blog before, as this is the site in the Delaware River where I sampled last year.

The water levels have been very low this year because we have largely not had any rain for weeks. This makes it easier for me to sample, but it is not usual for the time of year. Normally at this time of year the rocks in the lower left of the picture would be completely covered by water.

Here is a view of the same stream just downstream from the bridge. This area should currently be covered in water and should look like this only in June as the trees go to work and the rain falls off.

More of the same really, but I plan to take a picture of the same location latter in the summer and in the fall.

 

This year I have added another color to my pallet. Last year I used red, yellow, and orange, but this year I will be using blue. You can see the syringes with the color ready to go above this already marked ammocoete.

A few ammocoetes be anesthetized before marking showing a good mixture of the sizes I encounter..

I don't know why I took this picture of the ammocoete upside down, but it is what it is now.

Following my marking of ammocoetes I went further down on the Delaware River to look for spawning adults. The water was still too cold, and adults will probably not move for another 2 weeks, but I wanted to check. Here is a picture of NY-17 passing over the Delaware River.

While I did not find any lamprey I did find a dead American eel (Anguilla rostrata). I do not know how this animal died as it had no obvious marks on its body. American eels were at one point extremely common everywhere in the US west of the Mississippi River, but including the mighty Mississippi. American eels may have made up 1/3rd of all the fish biomass of the US when Europeans first arrived. Sadly eels are relatively rare now, although you can find them their populations are doing quite poorly, and there is even some attempt to list them as an endangered species.

 Here is the stream I work on in the Hudson River. I actually do not work here, but the picture is from the head waters of the stream at the park I stayed overnight at when I arrived. Sea lamprey may have used these sections of the stream in the past (although I suspect not), but currently a dam much further down gives them only a small section of stream (just a few miles) to spawn and rear in.

Sorry for the lack of Hudson River pictures. At the time I was working to go through as many animals as possible and I was alone so I was quite busy. Hopefully next time I will have time to take lots of pictures of the site.

First sampling event of the year

And so it begins...The field season is upon us, and noticeably so with such high temperatures. Have a look at my selection of lamprey pictures from the Genesee River. Lampreys were everywhere when we sampled, they actually swam by us as we worked. The adults will be out for 1-2 more weeks before they die, but not before they spawn.

An animal from last year that we found this year! I was surprised we recaptured an animal after so long.

Here is another animal from last year, in fact this animal is from June of 2014, and it has literally not moved since then.

I had quite a bit of help this time out, John (an undergraduate at ESF) did anything and everything in preparing and marking the lamprey.

We found more injured and unusual ammocoetes than I have ever seen. Here is an ammocoete with an infection that resulted in tumors growing on it. Zoom in to see more. 

Here's John again, weighing lamprey as I prepare to mark them.

Here is the difference between the last year of the ammocoete's life. On the top is an ammocoete probably 1 year older than the ammocoete on the bottom, but note how fat it is. In the last year of life the ammocoetes stop growing and begin to put on weight so they can migrate and spawn. Next spring this animal will, if it survives, attempt to spawn and make its own little ammocoetes.

A view downstream of the shot I enticed facebook viewers with to come visits the blog.

We encountered at least 2 ammocoetes that had been bitten. You can see the little jaw marks and also the nice bit of ammocoete skin and gill that was removed when the predator grabbed the animal. Luckily, at least for now, the ammocoete survived the encounter. Whether it survives until latter in the summer we will have to wait to see.

Wednesday was cloudy and cool, but Thursday was bright, warm, and sunny. Here is a good view looking downstream. The plants are starting to grow, but you can still see the bridge from the stream at this point. By July the trees will all but cover the road.

John weighing yet another lamprey we collected.

Me marking up the last lamprey and pretending that I did all the work.

The lamprey processing station with many lampreys read to go and one on the scale. The animals are anesthetized in clove oil before we begin.