Conserve Wildlife Blog

Posts Tagged ‘Menhaden’

Brood Reduction: New Jersey Osprey Cams Shine Light on Prey Availability

Tuesday, July 18th, 2023

by Ben Wurst, Senior Wildlife Biologist

Depending on where you look and who you talk to, the fate of many osprey nests might bring tears to your eyes. Since a nor’easter impacted the coast with strong onshore winds for several days, young ospreys have been dying of starvation in plain sight. Over the past week, several reports of adults who abandoned their nests with young have been received. This year, weather has impacted the availability of fish and outcomes of nests in the Garden State.


Help Ensure Ospreys Have a Future in New Jersey

Tuesday, September 26th, 2017

ACTION ALERT: Support ecological management of the most valuable public resource for our coastal ecosystem and economy

by Ben Wurst, Habitat Program Manager

Menhaden is a common food source for ospreys during their nesting season in New Jersey. Photo by Northside Jim.

The Atlantic States Marine Fisheries Commission is accepting public comment on the establishment of ecological management of Atlantic menhaden (Brevoortia tyrannus), which is a keystone species. Basically, a keystone species is one that plays a large role in the ecosystem where it lives. If a keystone species is lost then the ecosystem would dramatically change or cease to function, causing widespread effects to other species that benefit. In New Jersey, ospreys have largely benefited from a healthy menhaden population as we’ve had relatively high reproductive rates (more than double what’s needed to sustain population) over the past decade. From 2006 to 2016, the population has grown by 30% and above the pre-DDT, historic milestone of over 500 nesting pairs. Around 82% of the state population of ospreys nests along the Atlantic Coast and we observe menhaden at a huge number of nests during our mid-summer surveys. If menhaden numbers drop, then we will likely see osprey numbers follow suite, as reproductive rates will decline, as they are in the Chesapeake Bay.


A healthy population

Monday, August 30th, 2010
Osprey numbers continue to rise

by Ben Wurst, Habitat Program Manager

Three osprey nestlings at a nest near Osbourne Island. © Eric Sambol

Ospreys are currently listed as a threatened species in New Jersey. They were first listed as endangered in 1974 after the state population declined to only 50 pairs, from over 500 prior to 1950. Ospreys have made a remarkable recovery in New Jersey thanks to biologists with the Endangered and Nongame Species Program (ENSP) and many volunteers. Surveys that help monitor the population were conducted in late June and early July.

Volunteers and biologists surveyed all major nesting colonies from Sandy Hook south along the Atlantic Coast to Cape May and west to Salem County. Ospreys almost exclusively nest on man-made structures including platforms designed specifically for them, cell towers, duck blinds, channel markers, and boat lifts. Surveyors visited these nest structures to observe whether or not they were occupied. If they’re occupied, then the number of young were recorded and the young were banded for future tracking with a USGS bird band. Preliminary results show that productivity rates are up for all nesting colonies except one (Sedge Island WMA). Since ospreys are predators, they are at the top of the food chain. They are considered to be an indicator species, or a species that is sensitive to changes in environmental conditions and can serve as an indicator of an unhealthy marine ecosystem. Basically, a healthy osprey population means a healthy marine ecosystem.

The climate during this summer has been the complete opposite as last year. It was hot, dry, and calm, with only a few severe storms with high winds that caused some nests to fail. Otherwise, fish stocks are plentiful, especially menhaden. This year many out-of-state commercial fishing boats have started fishing for bunker off New Jersey waters. This is mostly due to declines in herring stocks in New England and the high demand for bait for use in lobster pots. State legislators have introduced a bill that would limit boats from catching bunker for use as bait. Read more here and this press release from the Recreational Fishing Alliance.

Full results from this years survey will be published soon in our annual newsletter. Here is last year’s newsletter.