A ray of hope for American shad
A hopeful sign about American shad was recently documented here in the Delaware River. The number of young-of-year (YOY) shad caught during targeted August-October sampling in the non-tidal Delaware River in 2017 set a new time-series high, a record dating back to 1988, according to provisional data provided by the Pennsylvania Fish and Boat Commission. Though this single data point should not allay concerns over the serious decline of the shad population from previous levels, it is at least one ray of hope.
The YOY American shad surveys are conducted in August, September, and October at six different sites spread out over nearly 200 miles of the non-tidal Delaware River. A 300-foot-long, boat-deployed beach seine net is utilized for this sampling, following prescribed sampling protocols. Four hauls are conducted nightly at each site beginning at sunset, as shad are rather light-averse fish and better catches occur after dark on a clear-flowing river like the Delaware.
The sampling, contributing to the non-tidal juvenile abundance index (JAI) of YOY American shad, provides data for comparison to a plan developed by the Delaware River Basin Fish and Wildlife Management Cooperative (https://tinyurl.com/ydhymnj8). Should the YOY shad non-tidal JAI fall below a pre-determined benchmark, management would be enacted to strengthen protection of the American shad population.
The seining surveys are carried out collaboratively by co-op member agency fisheries staff from agencies including the National Park Service, Pennsylvania Fish and Boat Commission, New York State Division of Marine Resources, U.S. Fish and Wildlife Service and many more. A significant number of volunteers, including high school and college students, also help out with these efforts.
Ed Wesely, one-time River Talk writer for The River Reporter, was present at the October 20 sampling and documented the procedure in the accompanying photos. He said, “I was particularly impressed by an easy-going professionalism that marked the seining phase, and again during the challenge of identifying and recording species and length for each fish among the hundreds seined.”
Notes of caution
The post-1988 record is welcome news, but must be considered in perspective. The commercial shad harvest on the Delaware River in the 1890s amounted to as many as five or six million fish, and that was only a fraction of the total run; the current population—even this year’s count—is considered stable, but at low levels. Juvenile production, assessed by seine net surveys in both non-tidal and tidal reaches over the past three decades, has varied without a discernable trend. Compare this to what locals observed in previous periods:
“I’ve looked in that river when the shad used to run full force. You’d stand on the bridge and look down and you could not see the water for the shad. It was just one solid mass of fish, and very dark. You wouldn’t even know this was water. We don’t get runs like that anymore…” (Russell “Doc” Homer, Lordville, NY, 1920-2001, National Park Service Interview, December 3, 1987).
Why care? The Delaware, like other rivers, evolved over thousands of years and became populated with plant and animal life supported by an annual pulse-of-life (in the form of sea-run migratory fish) that greatly benefited the river and its biota. These fish are a storehouse of carbon, energy and nutrients amassed from their multi-year ocean odyssey, whose spring spawning run provides nourishment that energizes the system and its inhabitants after a spare winter, and coincides with critical reproduction periods for other wildlife. Shad are eaten by eagles and multiple other animal species during a time of greatest provisioning need for their growing young. Millions of broadcast shad eggs are also consumed by fish and other aquatic life, and decomposing shad provide nutrients that enhance the growth of aquatic vegetation, which in turn is fed upon by macro-invertebrates and other biota. Millions of young shad also provide an abundant food source for everything that preys upon small forage fish in the Delaware River during the summer months. And come fall, out-migrating YOY shad in turn feed ocean fisheries, balancing an age-old cycle and completing an important ecological link that benefits both realms.
As we enter the darkest time of the year, perhaps this encouraging news about a record catch of YOY shad in the river this fall will spark a glimmer of hope for brighter days ahead. We’ve sent off a robust cohort of promising YOY shad, nurtured and made strong by their six months in our healthy river. After a few years we’ll hopefully be rewarded by the return of an abundance of resolute adult shad.
[Don Hamilton is Natural Resources Chief for the Upper Delaware Scenic and Recreational River.]