Tuesday, July 30, 2013

Cedar Pond Brook (Lowland Town Park)

We sampled in Cedar Pond Brook in Stony Point at Lowland Town Park on Monday.


There we found a wide array of invertebrates including some of the largest stoneflies I have ever seen. These stoneflies were Perlidae, and appeared to be Agnetina (although it would be best to see them under a scope to be sure). Stoneflies are considered good indicators of water quality, because they are often sensitive to pollution or sedimentation. After we finished with the invertebrate surveys we looked for lampreys and found an ammocoete within the park in less than 10 minutes!

Sea lamprey are known from this river (link) but their extent and distribution is largely unknown. In addition, we also found generous amounts of trash (usually aluminum cans). Please do not treat streams and rivers as disposal sites. High quality habitats are rare, and they could be in your backyard, even in places that you may visit daily! We continue on, and hope to find lamprey at one more site this week. More updates if we succeed or fail, and more pictures to come.

Saturday, July 20, 2013

Stockport Creek

Sorry for the long delay in blog posts. A wedding and lots of sampling has gotten in the way of the blog. We returned to the Hudson River this week, and amongst other sites we visited Stockport Creek.
Stockport Creek has a large delta with numerous small braids and islands that greatly increase habitat complexity and offer excellent habitat to many species. Once you get over the rapids (pictured behind the bridge) you move from the tidal delta into a clear water stream that slowly meanders through the country. We initially sampled below the bridge at a sandbar created by fallen wood.
While working we found an empty mussel shell partly buried in the sediment. The shell belongs to a native species of mussel, which are often critically endangered. Our native freshwater mussels (not our zebra/quagga mussel invaders) are fascinating creatures that utilize fish hosts when they are larvae. As adults they live a sedentary life of filter feeding, but come spawning season they utilize lures to attract hosts for their larvae. You can start reading more about them here: http://www.fws.gov/midwest/endangered/clams/mussels.html
We moved upstream the following day to sample where the Stockport Creek branched into the Kinderhook and Claverack Creek. We looked for lampreys in both streams, but did not find any. However, both streams appeared to be in good health (especially at the Kinderhook). Water temperatures in both branches were too high for lamprey, but we were unable to sample higher up in both streams. Upon return we ran into an individual who worked on a dam in the Kinderhook and reported that sea lamprey were sometimes present there, but have not been around at least for a few years.
Maybe lamprey occasionally spawn in Kinderhook when they can get past the dam. Hopefully next week I will have more time to upload the blog and continue to add pictures. Until then if you have any reports of sea lamprey in the Hudson River please leave a comment where you think you saw them and approximately when. Thanks!