***NFC Executive Director Bob Mallard (red shirt) and Max Rome of Charles River Watershed Association (waders) looking at structure that has fallen into Cheesecake Brook from above…***

Prior to NFC’s involvement in Cheesecake Brook in Newton, Massachusetts, this heavily altered urban stream was believed to be fishless. As a result of trapping, seining, and e-fishing, we have confirmed the presence of fish in Cheesecake Brook both upstream and downstream of a cement slab near where the stream empties into the Charles River. The cement slab is thought to be an impediment to upstream fish passage. To date, NFC and our partners have confirmed the presence of native white sucker, nonnative carp, and native catadromous American eel.

NFC and our partners from Charles River Watershed returned to Cheesecake Brook to try to capture some more fish. The goal was to increase our understanding of the fish species assemblage and abundance in Cheesecake Brook upstream of the cement slab. We are looking to better understand the relationship between the stream and river and ascertain to what degree the cement slab is blocking upstream fish passage.

***MA NFC Chair Paul Roell sampling Cheesecake Brook downstream of the cement slab…***

While walking Cheesecake Brook in Albemarle Park, NFC observed far more fish than we believed were present in the stream. Schools of up to 20 fish or more were observed from just below Watertown Street all the way down to the cement slab. Interestingly, very few lone fish were observed. And while American eel had been captured while e-fishing, none were observed while we were there, likely due to their nocturnal habits. Most of the fish observed were in slower and deeper pools.

Upon arrival, the group set several minnow traps in hope of capturing some fish. They then seined and netted several short sections of stream roughly mid-point in the park. The group was able to capture one juvenile native white sucker and one juvenile nonnative carp. Both species of fish have been previously documented upstream of the cement slab in Cheesecake Brook, along with American eel.

Seining proved more difficult than was anticipated. This is likely due to the schooling nature of the species of fish we encountered. When one flees, they all flee… While we were not able to capture any fish using the seining net, Spencer Belson from NFC and Max Rome from CRWA were able to capture one fish each using long handle dip nets.

Observations:

Large clods of dirt and grass that have fallen into the stream from the walls above have created some level of sinuosity and in-stream structure, while speeding up the current and providing cover refuge habitat for fish. Allowing this structure to remain in the stream, and ideally increasing it, would be good for fish and other aquatic lifeforms.

While amphibian life appears to be in relatively low abundance in Cheesecake Brook, aquatic insect life is notably abundant based on incidental capture while netting fish. When the nets were emptied, the organic matter scooped up from the streambed was literally teaming with insect larvae. As our focus was fish, we did not attempt to identify the insect life.

Next Steps:

NFC would like to schedule some additional e-fishing as it is by far the most effective method for capturing fish. The focus would be on the section of stream between the foot bridge across from the ballfield in Albermarle Park and Eddy Street. We would also like to survey some water upstream of Eddy Street where the habitat changes notably from that found in Albermarle Park.

We also believe that we could try some different seining/netting tactics to improve our catch rate. Specifically, we would use a weighted down fixed stream width seine net with a 2-3’ upstream apron in conjunction with a portable net mounted to vertical poles to corral the fish into the downstream fixed net. Some overnight minnow trap sets would be helpful as well.

NFC believes that the best opportunity to view American eel would be at night due to their nocturnal feeding habitats. We are looking to do some night visual surveys aided by the placement of dead fish in the stream in advance to lure eels in. Setting traps baited with dead fish overnight would help detect eel as well. If successful, we believe that evening “eel tours” would be a good way to engage the public and draw attention to this unique catadromous fish…

Opportunities for Fish Habitat Improvements:

While the cement slab may not be blocking upstream fish passage all the time, we believe that it is impeding such at certain flow levels, as well as for certain species. For example, we have captured 2 species of sunfish downstream of the cement slab, while none have been encountered upstream of it up to this point. This is likely due to their tall narrow profile, and the fact that they use their fins, not tail to propel themselves through the water.

Clearly, it would be very beneficial in regard to upstream fish passage if there were a fish ladder on the cement slab. NFC would like to try a proof-of-concept exercise using a temporary fish ladder and a monitoring video camera to see if we could pass fish upstream of the cement slab at various water levels.