A Look Back at the Data: August Historical Seining Results

Pictured above - A white sucker caught during one of our seining programs.

As CURB’s seining season continues to be on hold due to the COVID-19 pandemic, we take our monthly look back at our historical seining data. This summary will be focused on August data that was collected from 2005 – 2019.

August continues the theme of increasing catch totals, which is clearly seen in the graph above. We started these summaries all the way back in April, when our average catch per program is about 18 animals. However, by the time we get to August that number rises to about 64. At the same time the water temperature in the Hudson River is typically on the rise. By August we can see water temperatures peaking in the 80 – 85 degree range. We also usually see the salinity (amount of salt in the water) hovering in the 10 – 15ppt range. Earlier on in the spring, this number is usually around 5 – 10ppt.

So what does all of this mean? In short, usually larger and more diverse catches during the month of August. We see many baitfish gathered along the warm waters of the Hudson River shoreline, and the increased salinity allows some more marine species to move into the area.

The chart above shows our catch (2005-2019) broken down by species. The one type of fish that clearly stands out is the Atlantic silverside. 4,440 of these schooling baitfish were caught over 15 years, or almost 300 per August. Also with high totals are moon jellies (1,350), striped bass (987), shrimp (878), and blue crabs (814).

About 34.8% of all silversides are caught during the month of August, 12% of moon jellies, 23.4% of striped bass, just 6.4% of shrimp, and 8.2% of blue crabs. One animal which has been mostly caught in August is the invasive Asian shore crab at 70%, though this is a rather small sample size.

Our August catches have been fairly steady over the years, but there are 2 seasons which stand out: 2010 and 2018. In August of 2010 we caught over 1,200 Atlantic silversides which contributed to that larger than normal total. In 2018, our higher catch was due to over 700 each of Atlantic silversides and moon jellies.

For a full look at the data, please check out the seining page of our website.