Lamprey Lust

May 26th, 8am

The morning after graduation, I hit the field to look for nesting Northern Rough-winged Swallows for one of my research projects. I had already surveyed the creeks and natural areas surrounding Ithaca, so it was time to turn my focus on the not-so-natural areas in downtown Ithaca itself. There are several main creeks running through Ithaca to empty out into Cayuga Lake. While these creeks run through beautiful gorges on their way downtown, in the city they are channeled by high concrete walls and degrade considerably in quality. Unfortunately, these walls host rough-wings that like to nest in the drainpipes all along their length, so that means I had to go get my feet wet downtown to find them.

My first stop was Cascadilla Creek, where it empties out of a gorge into its walled channel on the edge of downtown. Last week I had scouted a pair of rough-wings using a drainpipe right near the entrance of the walled channel. It's a really pretty area so I was hoping to get a nest here, but the birds present a week ago had vacated the area. While wading across the creek to check the drainpipe just to be sure, a golden serpent-shaped critter went cruising by with the downstream current. I chased after it, initially thinking Nerodia, but the unique wavy dorsal-caudal fins made me quickly realize I was chasing a lamprey... cool! I had only seen one lamprey before, a brook lamprey species in a tributary of the Allegany River last year, but I didn't have my camera to take pictures to identify it later. I really wanted to catch this one and ID it, but I missed it and it carried on downstream.

Minor editorial note: I've been playing with blip.tv for my videos (the quality seems better than youtube) but the embedded player here allows you to flip through all of my uploaded videos. Feel free to watch them but just don't get confused if it is not the video I intended it to be.

I was a little bummed, and turned to head back upstream, out of the walled portion of creek to climb out and check a few more creeks for rough-wings. On the way though, I climbed up a small (~2 foot) waterfall right at the entrance to the walled portion of the creek... and saw another lamprey, fighting the current and looking to head upstream:

The water is so shallow around this waterfall that I was able to literally stand over them as up to three lamprey of various sizes thrashed around fighting to get upstream. While I wanted to get a picture of the rasping disc to confirm the species by dentition, the large size, golden color, and blotched markings all confirmed these as Sea Lamprey (Petromyzon marinus), an invasive species in the Great Lakes watershed. I knew they had also made it into Cayuga Lake of the Finger Lakes watershed, but I had never even thought that I would ever encounter one. Well, here were three, attempting to make a spawning run.

I made several attempts at grabbing the lamprey to get a picture of the dentition, but these things are slippery and squirmy and they just shoot out of your hand. Two of them swam into the nearby deeper pools to evade me, but one continued to swim in the shallows and even started to spawn. Of course, he was spawning alone so I don't know what good it would do, but it was really neat to see and film. Watch for the rapid vibrations at 0:30:

After a good fifteen+ minutes of intense lamprey-watching, the call of the rough-wing forced me to continue on my searches downtown for a nest. For the next two hours I wandered down the length of Cascadilla Creek before hopping over to Six-Mile Creek, the next creek south, and at least twice the size of Cascadilla. Here I started fairly downstream on its downtown course, a little before it begins to deepen into a channel and enter the Cayuga Lake inlet. I started off walking along a grassy park that borders the creek wall, scanning for more pipes and approaching a pipe I knew has had birds previously. A splash called my attention to a Great Blue Heron (Ardea herodias) just downstream. I froze, because he had something good in his mouth. I very quickly but quietly removed my camera from my pack (I could tell the Heron was aware of me and ready to bolt), and managed to snap this series. I don't think I need to narrate it.

Another lamprey, and a Huge one! This was turning into quite a morning for them. I started looking around in the nearby shallows and saw one, then another lamprey swimming around. I saw one in the distance associating with what could be a nesting depression, so I thought 'this is fantastic' and had to get in the creek with them. I walked upstream to one end of the park, where a ramp allows access into the creek bottom. Right at the base of the ramp, in water just a few inches deep, was an awesome sight - three lampreys going at it in a spawning bed, including a big, golden male. I got my best pictures yet, and a whole bunch of video of the process.

In this first picture, the big golden male is in the center. Males are supposed to attain the brighter colors during spawning, as well as developing a weird ropey ridge along the back, visible in some of the following pictures. I didn't get any video of the actual nest construction, but these guys actually build their depressions by moving stones with their oral discs. The female then attaches herself to a rock, the male wraps around her, and they deposit their future offspring in the silt of the nest.

In this picture, you can see the third, pineal eye on top of the head:

Some video:

After watching these guys for another length of time, I once again had to continue my search for nesting rough-wings. I entered the shallow creek bed here and began walking upstream, where the walls get higher and higher but the creek remains fairly broad and shallow, great for walking and great for spawning lamprey in the shallow rocky riffles. I found several more nests, and several individuals cruising about. One nest even had four lamprey in it.

Over the course of that day and the next week I spent in Six-mile Creek observing rough-wings, I also observed the after-effects of the lamprey spawning rush: death. Like other mass-spawning fish such as salmon, the lamprey die soon after spawning. I saw many individuals cruising around awaiting their fates, and found fresh bodies. They get so much action but at such a cost... it makes me glad humans are iteroparous breeders.