osprey Archives - Saving Seafood

Ocean Harvesters disputes osprey-menhaden link

June 18, 2026 — A scientific paper documenting widespread reproductive deficits among Chesapeake Bay osprey is drawing attention from the commercial fishing industry, with Ocean Harvesters arguing that the study does not establish a causal link between the declines and Virginia’s commercial menhaden fishery.

The paper, Widespread Reproductive Deficits in Chesapeake Bay Ospreys, published in Frontiers in Marine Science, suggests that reduced availability of Atlantic menhaden may be a primary factor contributing to poor osprey nesting success in high-salinity regions of the Chesapeake Bay.

In a June 11 email statement provided by Ocean Harvesters, they claimed the study raised important question about osprey productivity but “does not prove that Virginia’s commercial menhaden fishery caused the problem.”

According to Ocean Harvesters, the paper relies on a series of inferences connecting poor osprey reproduction to food stress, reduced menhaden availability and ultimately commercial fishing activity, but stops short of demonstrating direct causation.

Peter Himchak, senior fisheries scientist at Omega Protein, also cautioned against interpreting the paper as definitive evidence linking the reduction fishery to osprey declines.

“This paper is likely to draw attention because it reads, at least up front, like an indictment of menhaden availability in the Chesapeake Bay,” Himchak said. “But the paper also details numerous other possible mechanisms that may affect osprey productivity, and those caveats are critical considerations in evaluating this issue.”

Read the full article at the National Fisherman

Chesapeake Bay Foundation’s Menhaden Blame Game Isn’t Backed by CCB Findings

October 8, 2025 — The following was released by Ocean Harvesters:

As Virginians, we share the public concern about the poor 2025 osprey breeding results reported by the Center for Conservation Biology (CCB). But the Chesapeake Bay Foundation’s (CBF) attempt to pin those outcomes on the menhaden fishery misstates the timeline, overextends the CCB advisory’s inferences, and ignores other environmental factors that CCB itself noted.

What CCB actually reported

CCB’s news advisory organizes 2025 results by salinity (used as a proxy for local fish communities) and finds that higher-salinity sites had low productivity while low-salinity sites exceeded population-maintenance thresholds. CCB explicitly states “salinity is a proxy for the fish community” and that ospreys in high-salinity areas are believed to rely more on menhaden. CCB also documents many pairs that did not lay clutches in 2025, arriving on time in late February-early March, then abandoning territories in significant numbers, with many returning in June (a first for the Bay population). Finally, CCB notes that food stress showed up as single-chick broods (67% of broods in waters with salinity levels above 5 parts per thousand) and widespread post-hatch losses.

A presentation given by US Geological Survey scientists to the Menhaden Board of the Atlantic States Marine Fisheries Commission in August 2024 shows that past research, including research by CCB Director Dr. Bryan Watts, identified other species as being the primary prey of osprey in the higher salinity areas of the Bay. To make the leap that menhaden is the singular problem is not supported by the data.

By Virginia law, purse-seine fishing for menhaden is closed until the Sunday before the first Monday in May (i.e., there is no fishing until early May).
According to Ocean Harvesters’ fleet logs provided to state regulators, menhaden fishing did not begin in the Bay until the week of May 26 in 2025, reflecting late arrival/availability of menhaden that is controlled by nature.
CCB states in a photo caption that: “Most young that starve in the nest die within the first two weeks after hatching.” If chicks hatch in April/early May, those deaths occur before fishing started.
CCB records pairs arriving late February-early March; many never laid eggs at all, events that obviously precede any fishing and indicate that birds may not return to the area in good health.

Taken together, CCB’s description of timing, plus the dates of the legal fishing season, make clear that early nest failures and the chick mortalities in the first two weeks after hatching occurred before the menhaden fishery began harvesting.

Where CBF goes beyond the CCB advisory

The Chesapeake Bay Foundation’s press statement asserts that CCB’s results “indicate insufficient local food availability in areas where the osprey diet relies on forage fish like menhaden.” CBF points to a decline in bait landings and juxtaposes those figures with the industrial reduction fishery’s annual catch to imply cause and effect.

That is CBF’s biased interpretation, not CCB’s conclusion. CCB does not directly blame the menhaden fishery; it infers food limitation from breeding metrics and salinity as a prey proxy.

CCB itself reports weather-related nest losses (high winds, extended rains) and notes that even low-salinity areas performed worse than recent years, evidence that multiple environmental drivers were at work in 2025.
Ospreys are generalist fish-eaters that take a range of species of suitable size; when menhaden aren’t present inshore, ospreys use other prey (e.g., gizzard shad, catfish). CCB’s map/photo captions and standard references reflect this dietary flexibility.
Fleet operations and observations indicate menhaden have arrived late in recent years, a function of environmental conditions, not fishing. The fishery has no mechanism to delay migration or in-Bay availability.
While menhaden bait landings may be lower in the Bay than in the past, CBF fails to consider the level of effort. There are documented instances of pound netters who have stopped fishing over the past few years through a combination of factors including higher costs for equipment and the inability to find dependable (and affordable) labor.
Bait landings reflect harvest effort and market conditions and are not a direct measure of local fish abundance or near-shore availability to osprey.

CCB’s 2025 advisory shows food stress signals in higher-salinity waters, but the timing and the text do not support CBF’s misleading narrative that the regulated menhaden fishery caused this year’s early nest failures and first-weeks chick mortalities. Those events occurred before the season opened and menhaden boats were still at the dock. Environmental factors, weather-driven nest losses (high winds/extended rains) and widespread post-hatch starvation, are plainly implicated in CCB’s account and must be part of any honest discussion, despite the self-interested view of a special interest group like the CBF.

About Ocean Harvesters
Ocean Harvesters owns and operates a fleet of more than 30 fishing vessels in the Atlantic Ocean and Gulf of Mexico. The company’s purse-seine fishing operation is exclusively engaged in the harvest of menhaden, a small, nutrient-dense fish used to produce fish meal, fish oil, and fish solubles. Both its Atlantic and Gulf Menhaden fisheries are certified sustainable by the Marine Stewardship Council. Committed to responsible fishing operations, Ocean Harvesters is proud to be heir to a fishing legacy that extends nearly 150 years.

VIRGINIA: Ocean Harvesters fight to keep fishing

September 29, 2025 — Virginia holds the distinction of being the largest East Coast state for seafood catch volume and the third-largest producer of marine products in the nation, surpassed only by Alaska and Louisiana.

This is largely tied to Reedville, Va. having historically been the fifth largest “volume of catch” commercial fishing port in the United States, and home to Omega Protein, Inc. and its fishing partner Ocean Harvesters.

The recent news that Ocean Harvesters is adding a $9 million menhaden vessel, the 165-foot F/V Tangier Sound, to its fishing fleet is sending a message that Ocean Harvesters, Omega Protein Inc. and Canadian parent company Cooke Inc. plan on fishing in the bay region well into the future.

The company has been dodging a barrage of opposition up and down the East Coast, ranging from Maryland 5th graders writing letters to the firm to “stop killing ospreys,” to opponents throwing blocks into nets. Tactics have included a jet skier interrupting net sets, protest boats attempting to block the fishermen, and environmental groups alleging that overfishing of menhaden is depleting osprey and striped bass populations.

A lawsuit in federal court for the Southern District of New York alleging that Cooke Inc. had been illegally fishing in U.S. waters because the boats are owned by a Canadian firm was dismissed in January 2025, allowing Ocean Harvesters to continue to fish.

The jet ski incident occurred in September 2023 and brought national attention to the debate, prompting Virginia legislators to pass a “right to fish” law to protect menhaden crews and commercial fishing watermen from harassment.

During a Sept. 15 tour of Omega Protein’s fish meal and oil plants and the new vessel, including a 45-minute ride on Tangier Sound and a three-hour classroom style seminar, Ocean Harvesters defended why reduction menhaden fishing should continue on Chesapeake Bay.

Ocean Harvesters’ CEO Monty Diehl addressed each issue with detailed graphic presentations aimed at countering growing opposition from environmental groups such as the Chesapeake Bay Foundation, as well as a swelling waterfront population whose changing demographics have no ties to the bay’s seafood or maritime culture.

Virginia has a small purse net bait recreational fishery that catches menhaden as well as the larger “reduction” fishery, so named because of how its catch is processed for omega fish oils, meal and related products. It is the only large menhaden reduction fishery remaining on the East Coast. The reduction fishery was founded in 1867 by Elijah Reed who brought the modern day pogy (menhaden) fishery to Virginia from Brooklin, Maine. Reedville is named after Elijah Reed and a monument in the town square memorializes that history.

Read the full article at National Fisherman

Ocean Harvesters Responds to Chesapeake Bay Foundation’s August 7 Press Release

August 8, 2025 — The following was released by Ocean Harvesters:

A press release issued yesterday by the Chesapeake Bay Foundation (CBF) continues a multi-year pattern of gross dishonesty, as it presented an incomplete and misleading narrative regarding menhaden management in the Chesapeake Bay. CBF’s misleading release includes a statement from Virginia Executive Director Chris Moore that ignores and disparages the established science, and the regulatory framework that ensures the fishery remains sustainable and responsibly managed.

In response, Ocean Harvesters has issued the following:

The CBF release refers to “growing warning signs around the Chesapeake Bay”:

“There are clear signs of peril in the Chesapeake, and menhaden are one of the connecting threads.“

This claim is not supported by any independent, peer-reviewed science, but rather represents the biased opinion of a special interest group. The assertion that “there are clear signs of peril in the Chesapeake, and menhaden are one of the connecting threads” overstates both the available scientific evidence and the known ecological dynamics of the Bay. While ecosystem concerns merit monitoring, attributing broad Chesapeake Bay challenges to already conservative menhaden harvest regulations is not supported by the best available science.

In 2024, the U.S. Geological Survey (USGS) presented data to the ASMFC on osprey populations which showed osprey reproduction challenges and nest failures occurring on both the Atlantic and Pacific Coast, including many areas with no menhaden fishery at all. In a letter to Congress earlier this year, USGS said it found no direct link between regulated menhaden harvests and declining osprey populations. The federal agency emphasized that multiple, complex factors, including weather, predation and prey access, contribute to ecological trends in the Bay.

Scientists from the U.S. Geological Survey present a slide to the ASMFC showing that the recent leveling-off in Maryland and Virginia osprey populations, after years of explosive growth, is a phenomenon also being seen in states across the nation, on both the East and West Coast.

Ocean Harvesters menhaden fishermen.

The statement includes: “This new timing of intense fishing pressure may be contributing to the problems facing the Chesapeake Bay.”

Any adjustment in the timing of Bay fishing is minor and reflects natural shifts in the seasonal population dynamics of menhaden, not a quantifiable increase in harvest pressure or ecological harm. No scientific evidence has established any link between this timing shift and the broad ecological challenges described in the release.

While the press release references anecdotal concerns from Maryland fishers, it omits mention of well-documented water quality issues in Maryland that may also explain the localized fishery observations cited.

Another claim in the statement reads: “One foreign-owned company consistently prevents progress in Virginia, and now coastwide at the ASMFC.”

This statement is inaccurate. Omega Protein is a Virginia-based processing company, and the menhaden are harvested by Ocean Harvesters, a separate American-owned and operated company whose crews are overwhelmingly local, unionized, and multi-generational, represented by UFCW Local 400, AFL-CIO. This domestic fleet works in full compliance with harvest controls, vessel reporting, and ecosystem-based management thresholds set by the ASMFC. CBF is clearly attempting to mislead the audience with distorted information and is crossing a very serious ethical line of misinformation that merits further scrutiny.

CBF’s repeated implication that the industry has obstructed scientific research misrepresents the actual facts. Ocean Harvesters supported a comprehensive ecosystem study of the menhaden fishery developed by the Atlantic States Marine Fisheries Commission (ASMFC) in 2021. However, the proposal that later emerged in the Virginia General Assembly used a lower cost, novel methodology that had not undergone scientific peer review. The industry raised legitimate concerns-not about research itself, but about relying on an untested approach for such a politically charged issue. CBF has repeatedly and inaccurately characterized this as blanket opposition to science. In fact, the industry continues to support the original, science-based study design developed by ASMFC, and no menhaden research could be conducted without longstanding industry cooperation.

The statement concludes: “The Chesapeake’s fisheries and predators can’t wait. Menhaden are key to a thriving Chesapeake Bay, and a healthy, productive Chesapeake is vital to the entire Atlantic coast.”

There is simply no Chesapeake Bay crisis that would threaten fisheries or predators. The menhaden fishery is already one of the most scientifically scrutinized in the United States.

The menhaden fishery is currently:

Not overfished, and overfishing is not occurring, as confirmed by repeated stock assessments.
Certified sustainable by the Marine Stewardship Council (MSC)
Governed by ecosystem reference points that account for predator-prey relationships
Subject to real-time reporting, seasonal harvest caps, and rigorous monitoring under ASMFC’s management plan

Here is the true threat: CBF’s statements add up to nothing more than scare tactics that threatens the livelihood of hundreds of blue collar, multi-generational employees, many of whom are minority and UFCW Local 400 union workers, in Virginia’s Northern Neck.

Omega Protein urges scientific review before menhaden fishery cuts

July 31, 2025 — Menhaden processor Omega Protein and its harvesting partner Ocean Harvesters have urged the Atlantic States Marine Fisheries Commission (ASMFC) to conduct further scientific reviews before considering potential reductions to the Chesapeake Bay menhaden fishery.

In a letter to the ASMFC, Omega Protein Senior Scientific Advisor Peter Himchak argued that recent concerns linking menhaden fishing to declines in osprey populations are being overstated, calling for a broader investigation into possible causes.

Himchak, a former fisheries biologist with the New Jersey Division of Fish and Wildlife and longtime advisor to the ASMFC and the Mid-Atlantic Fishery Management Council, criticized what he called an “inordinate amount of focus on menhaden generally, and the reduction fishery in particular,” in discussions of osprey declines.

In particular, he pushed back against recommendations made by the ASMFC’s Work Group on Precautionary Management in the Chesapeake Bay, calling them “draconian” and warning that implementing restrictions without clear evidence of depleted menhaden stocks or proven impacts on osprey risks harming an industry that supports hundreds of jobs and has operated for over 150 years.

Read the full article at Aqua Feed

Omega Protein and Ocean Harvesters Urge Science-Based Review Before Imposing New Menhaden Restrictions

July 29, 2025 — The following was released by the Menhaden Fisheries Coalition:

In a letter submitted to the Atlantic States Marine Fisheries Commission (ASMFC), Peter Himchak, Senior Scientific Advisor to Omega Protein, warned that “there has been an inordinate amount of focus on menhaden generally, and the reduction fishery in particular” in discussions about recent osprey declines in the Chesapeake Bay.

Omega Protein, which processes menhaden into fishmeal, fish oil, and related nutritional products, is supplied by Ocean Harvesters under a long-term harvesting agreement. Himchak submitted the letter on behalf of the company ahead of the ASMFC’s Summer Meeting.

Himchak, who served for 39 years as a fisheries biologist with the New Jersey Division of Fish and Wildlife and as a long-time advisor to both the ASMFC and the Mid-Atlantic Fishery Management Council, sat on the ASMFC’s Atlantic Menhaden Technical Committee and Stock Assessment Sub-Committee from 1988 until 2006.

In the letter, Himchak criticized the ASMFC’s Work Group on Precautionary Management in Chesapeake Bay for proposing “draconian management recommendations ‘without determining if there is or is not an adequate supply of menhaden to support predatory demand in the Bay.’” He warned that moving forward with such actions without first determining whether there are, in fact, fewer menhaden in the Bay or whether the fishery has any impact on osprey “risks gravely impacting a more than 150-year-old industry and hundreds of jobs while doing nothing to improve the osprey situation.”

Himchak wrote that the ASMFC’s Technical Committee (TC) already has a significant workload in advance of the Commission’s Annual Meeting, but raised four areas of scientific inquiry the TC could investigate that would provide the Board with more complete information. 1) He asked whether “the phenomenon of reduced osprey production [is] confined to the times and areas in which the menhaden reduction fishery operates,” referencing USGS data showing declines in osprey abundance in coastal areas of multiple states—not just the Chesapeake—and increases in interior regions. He also noted that the fishery does not begin fishing until May or later—after migrant ospreys arrive in the region from late February to early March and begin building nests from mid-March to mid-April—raising questions about how the fishery could influence osprey’s months-earlier decisions about where to nest.

2) He wrote that there have been sizable increases in populations of multiple menhaden-dependent predators since at least the turn of the century, and that a stomach contents analysis of striped bass, which are only somewhat dependent on menhaden, indicated they “are not starving and would be considered healthy.” Therefore, he asked, “is it more likely that ospreys are being outcompeted or that the reduction fishery uniquely impacts osprey?”

3) Regarding eagle-osprey interactions, he noted a recent Maryland DNR release announcing “large increases in the state’s bald eagle population.” He referenced myriad studies finding that bald eagles are “kleptoparasitic”—a term used to describe their well-documented habit of attacking hunting osprey to steal their food or prey on adults, young, and eggs. Citing a study from Voyageurs National Park, he wrote that “increased numbers of eagles were associated with a reduction in the numbers of osprey nests, their nesting success and heronry size,” and asked whether “issues of competition and depredation [can] be ruled out as a cause of osprey’s lack of breeding success.” He further pointed to “significant scientific and anecdotal evidence of the dominant and adverse impacts eagles have on osprey.”

That concern was echoed in a newly released Saving Seafood special report titled “Bald Eagle Recovery in Chesapeake Bay Raises Red Flags for Osprey.” The report compiled over three decades of peer-reviewed research, field observations, and published accounts documenting instances in which eagles had a negative impact on osprey populations. In one study, researchers found “eagle abundance was negatively associated with nest reuse (i.e., persistence) and success of ospreys.” Significantly, the researchers found “little evidence of bottom-up limitations,” such as poor weather or declining fish stocks, and emphasized the role of eagle aggression, including harassment and food theft. While this body of research does not prove the resurgence of bald eagles in the Chesapeake to be the cause of osprey reproduction issues, it does indicate it is a possibility deserving of further investigation.

The full report is available at: https://www.savingseafood.org/science/bald-eagle-recovery-in-chesapeake-bay-raises-red-flags-for-osprey

4) Himchak also asked the Technical Committee to consider whether osprey foraging success is being affected by climate-driven environmental changes, including storm frequency, shoreline hardening, warming waters, or hypoxia. Citing a 2024 study by Bryan Watts, he noted that “deliveries of all forage species to osprey nests declined steadily from 1974 to 2021,” and asked whether “ospreys’ apparent lack of foraging success is tied to changes in local conditions that are impacting either local abundance of forage or osprey’s hunting success.”

He concluded the letter by writing, “The commission must be guided by science. Precipitous actions, taken in the name of precaution, are not always harmless. Neither Ocean Harvesters nor Omega Protein can survive without the current low level of access to the menhaden resource in the Bay. There simply are not enough ‘fishable days’ – that is, days where the weather and sea conditions allow vessels to operate – in a year to safely conduct a profitable fishery solely in the ocean. The menhaden fishery is managed in the most conservative manner in its 150 year or so history, and the reduction fishery is operating at its lowest sustained levels – in the Bay and overall – for as long as we have reliable records (i.e., since the 1950s). Precaution is already the policy. Before taking actions that could cause irreversible economic harm to this historic fishery, the Board should ensure that all reasonable avenues of inquiry into the issues facing osprey are explored.”

About the Menhaden Fisheries Coalition
The Menhaden Fisheries Coalition (MFC) is a collective of menhaden fishermen, related businesses, and supporting industries. Comprised of businesses along the Atlantic and Gulf coasts, the Menhaden Fisheries Coalition conducts media and public outreach on behalf of the menhaden industry to ensure that members of the public, media, and government are informed of important issues, events, and facts about the fishery.

Bald Eagle Recovery in Chesapeake Bay Raises Red Flags for Osprey

July 28, 2025 – The Chesapeake Bay is once again teeming with bald eagles, a testament to decades of successful conservation efforts. A recent feature by the Maryland Department of Natural Resources (DNR), “A Soaring Success: Maryland’s Bald Eagle Population Recovery” by science writer Joe Zimmermann, highlights this remarkable comeback.

In 1977, a mere 44 breeding pairs of bald eagles were recorded in Maryland. Today, that figure has soared to over 1,400, according to estimates from the Maryland Bird Conservation Partnership. This dramatic rebound has established the Chesapeake Bay as a national stronghold for bald eagles, boasting the highest concentration of breeding pairs outside Alaska.

This recovery is largely attributed to sustained, science-driven policy. The 1972 federal ban on the pesticide DDT, which caused reproductive failure and eggshell thinning, was a pivotal moment. In Maryland, the 1984 Chesapeake Bay Protection Act further safeguarded critical habitat within 1,000 feet of tidal waters. These combined measures helped restore nesting conditions and bolster survival rates.

The scale and speed of this recovery have made bald eagles a symbol not just of national pride, but also of effective conservation action. “Bald eagles are a very good example of what happens when you find the solutions and take action, and now you can look at how they’ve come back,” said DNR conservation ecologist Dave Brinker.

Today, bald eagles nest in every Maryland county and in Baltimore City. The Bay supports not only year-round resident eagles but also seasonal visitors from both the North and South. “Through the year, we have three pretty unique populations of bald eagles,” Brinker explained. “There are local birds that are here all year long. Then southern breeding eagles disperse to the Chesapeake Bay to spend summer here because food resources are so good. And in the winter, northern populations that need a warmer place, they come down to the Chesapeake Bay.”

Bald Eagle Recovery and Its Interspecies Consequences

While the recovery of the bald eagle in North America, particularly along the Chesapeake Bay, is a significant conservation milestone, its resurgence raises questions about its impact on other piscivorous bird species that have also been rebounding from decades of decline. Chief among these is the osprey, a fish-eating raptor that shares habitat and prey with bald eagles throughout coastal and inland waters. The Chesapeake Bay, now home to one of the largest bald eagle populations in the continental United States, is also crucial osprey habitat, making it an ideal region for observing interactions between the two species.

In recent years, environmental organizations like the Chesapeake Bay Foundation and sportfishing advocates such as the Theodore Roosevelt Conservation Partnership have repeatedly claimed that industrial menhaden fishing is the primary driver of osprey reproductive failures in the Bay. Their public campaigns, regulatory letters, and media statements link declining nest success to a perceived, yet scientifically undocumented, drop in Atlantic menhaden availability—a key prey species for ospreys during chick-rearing season. Much of this advocacy draws on research by Dr. Bryan Watts of the Center for Conservation Biology at William & Mary, whose studies have indicated increased nest failure in parts of the lower Chesapeake. However, even Watts has cautioned against definitive conclusions. In a 2024 Associated Press article, he stated, “We do not know why menhaden have become less available to osprey,” and suggested climate change as a possible factor.

Beyond climate shifts, other ecological dynamics may be at play, but the menhaden-focused narrative has recently overshadowed attention to other potential pressures. Given the Maryland Department of Natural Resources’ announcement that the Bay now hosts one of the nation’s largest bald eagle populations, interspecies competition deserves closer scrutiny—particularly food competition stemming from kleptoparasitism, the well-documented behavior in which eagles steal fish from ospreys. These interactions, studied for decades by field biologists and ornithologists, warrant renewed attention in light of the bald eagle’s increasing population.

While the ecological relationships between bald eagles and ospreys are not yet fully understood, evidence from multiple regions suggests that competitive pressures—especially kleptoparasitism and nest harassment by eagles—may hinder osprey nesting success in areas with high eagle densities. It is possible that the recovery of one iconic raptor is, in part, coming at the expense of another. These dynamics deserve greater consideration from scientists, wildlife managers, and policymakers.

Top-Down Pressure: A 35-Year Body of Research Shows Bald Eagle Competition May Threaten Osprey Nesting Success

As bald eagle populations have steadily rebounded across North America, particularly in strongholds like the Chesapeake Bay, a longstanding body of scientific research suggests that their recovery may come at the expense of other raptors, especially ospreys. For more than three decades, field biologists and ornithologists have documented the effects of interspecific competition and kleptoparasitism, the act of stealing food, as a factor contributing to osprey nesting failures.

One of the most comprehensive analyses of these dynamics comes from a 2019 study published in the Journal of Animal Ecology titled “Top-down effects of repatriating bald eagles hinder jointly recovering competitors.” Led by Jennyffer Cruz and co-authored by Steve K. Windels, Wayne E. Thogmartin, Shawn M. Crimmins, Leland H. Grim, James H. Larson, and Benjamin Zuckerberg, the study evaluated 26 years of nesting data in Voyageurs National Park, Minnesota. The researchers found that as bald eagle numbers increased due to intensive protections, the populations of ospreys and great blue herons declined.

“Bald eagles are top predators and a flagship species of conservation that have benefited from intensive protection,” they wrote, “but this likely hindered the recovery of ospreys and herons.” The study documented that “eagle abundance was negatively associated with nest reuse (i.e., persistence) and success of ospreys,” and concluded: “The top-down effects of returning bald eagles were the main predictors of declining nesting demographics for ospreys and herons resulting in their failed recoveries.” Importantly, the authors found “little evidence of bottom-up limitations,” such as poor weather, habitat loss, or declining fish stocks, implicating competition and interference from eagles as a primary driver.

The literature documenting these dynamics stretches back decades.

In a 1994 field note published in The Journal of Raptor Research, Professors J. MacDonald and N.R. Seymour of St. Francis Xavier University in Nova Scotia documented a lethal encounter in which a bald eagle pursued and killed an adult male osprey that was carrying a white perch. A second eagle joined the chase, and after a brief pursuit, one eagle seized the osprey midair, dragged it to shore, and ate it. The authors believed the attack originated as an act of kleptoparasitism—food theft—a behavior they note is well documented between eagles and ospreys and which they described as “a common occurrence.” They also referenced a second lethal attack, described by Flemming and Bancroft in 1990, in which a bald eagle attacked an osprey nestling shortly after it had received a fish.

In 2013, four U.S. Army Corps of Engineers (USACE) staff members working at Lake Sonoma in Geyserville, California, documented what was believed to be the first officially recorded case of “cooperative kleptoparasitism” in which a pair of bald eagles worked together to steal a fish from an osprey. Their observations were formally published in 2014 in The Journal of Raptor Research and summarized in a March 20, 2014, article on Army.mil, which likened the coordinated and calculated nature of the predation to something out of Jurassic Park. “Rarely have humans seen them cooperating to hunt as a pair,” USACE ecologist Wade Eakle explained. “This was the first time we witnessed them actually cooperating to steal, from another species.” The two eagles forced the osprey to drop its trout, after which the larger female swiftly seized the fish and flew off. Rangers had been monitoring the nesting pair since 2001, but this behavior marked a milestone in understanding the extent of eagle dominance over other raptors.

Evidence for this behavior also includes a 1988 study by Dennis G. Jorde and G.R. Lingle, published in the Journal of Field Ornithology, which observed repeat patterns of interspecific kleptoparasitism along the Platte River in Nebraska. Their findings indicated that bald eagles not only routinely stole food from other raptors but developed learned strategies for doing so efficiently, particularly during important foraging periods.

Even outside peer-reviewed journals, naturalists and field reporters have provided consistent anecdotal corroboration. BirdWatching Magazine similarly observes: “Bald Eagles are known to steal fish from other birds, particularly Ospreys. They will aggressively chase Ospreys in flight until the Osprey drops its catch, which the eagle will then snatch midair or retrieve from the water.” Another article in the same publication added, “It is common for ospreys and eagles to be in the same hunting grounds. As the more aggressive raptors, eagles will often fight the Osprey and force it to let go of the captured prey. The eagle will typically swoop in to catch the stolen prey.” The Cornell Lab of Ornithology’s All About Birds guide echoes these observations: “A Bald Eagle will harass a hunting Osprey until the smaller raptor drops its prey in midair, where the eagle swoops it up”, a classic example of kleptoparasitism.

Collectively, these studies and field reports spanning decades point to a clear and well-established pattern: as eagle populations recover and concentrate in resource-rich areas like the Chesapeake Bay, their aggressive behavior and dominance in the food web may have measurable negative consequences for ospreys. The repeated harassment and food theft increase energetic costs for osprey parents, reduce feeding efficiency, and may contribute to nest failures.

While the recovery of the bald eagle in the Chesapeake Bay region is unquestionably a landmark conservation success story, it does not exist in ecological isolation. As concerns continue to emerge about osprey reproductive success in key habitats like the Bay, it is increasingly important to view this predator’s return within the broader dynamics of interspecies competition. Over the past 35 years, a robust and diverse body of scientific literature—supported by peer-reviewed studies, field notes, and firsthand accounts—has documented the kleptoparasitic behavior of bald eagles, particularly their tendency to steal fish from ospreys and, at times, directly harass or even kill them. This behavior, while natural, may contribute to the energetic costs and nest failures observed in osprey populations where eagle densities are high.

Even Benjamin Franklin, in an often-cited letter, criticized the selection of the bald eagle as the national bird due in part to its scavenging habits and its theft of fish from “the fishing hawk,” known today as osprey.

For my own part I wish the bald eagle had not been chosen as the representative of our country. … he watches the labour of the fishing hawk; and when that diligent bird has at length taken a fish, and is bearing it to his nest for the support of his mate and young ones, the bald eagle pursues him, and takes it from him.

While his concerns were framed with a satirical flourish, he anticipated a tension now supported by decades of ecological research. As wildlife managers and policymakers evaluate recent reports of declining osprey productivity, it is essential that they consider not only fishery-related factors but also the well-documented competitive interactions between these two raptor species.

References

BirdWatching Magazine. (2025, March 7). What time of day do Osprey hunt? BirdWatching Daily. https://www.birdwatchingdaily.com/beginners/birding-faq/what-time-of-day-do-osprey-hunt/
BirdWatching Magazine. (2025, May 19). What do Bald Eagles eat? BirdWatching Daily. https://www.birdwatchingdaily.com/beginners/birding-faq/what-do-bald-eagles-eat/
Cornell Lab of Ornithology. (n.d.). Bald Eagle – Life history. All About Birds. Retrieved July 23, 2025, from https://www.allaboutbirds.org/guide/Bald_Eagle/lifehistory
Cruz, J., Windels, S. K., Thogmartin, W. E., Crimmins, S. M., Grim, L. H., Larson, J. H., & Zuckerberg, B. (2019). Top-down effects of repatriating bald eagles hinder jointly recovering competitors. Journal of Animal Ecology, 88(12), 1792–1804. https://doi.org/10.1111/1365-2656.12990
Eakle, W. L., Lishka, J. J., Kirven, M. N., & Hawley, J. (2014). Cooperative Kleptoparasitism by a Pair of Bald Eagles at Lake Sonoma, California. Journal of Raptor Research, 48(1), 89–91. https://doi.org/10.3356/JRR-13-45.1
Flemming, S. P., & Bancroft, R. P. (1990). Bald eagle attacks osprey. Journal of Raptor Research, 24(2), 122. https://sora.unm.edu/sites/default/files/journals/jrr/v028n02/p00122-p00122.pdf
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VIRGINIA: Menhaden Fisheries Coalition Denies Contributing to Osprey “Population Collapse” on Virginia’s Eastern Shore

July 1, 2025 — The Menhaden Fisheries Coalition has responded to the Chesapeake Bay Foundation’s claims of industrial menhaden fishing contributing to a “total population collapse” of osprey on Virginia’s Eastern Shore.

This comes after a May survey by the College of William and Mary’s Center for Conservation Biology reported a 90% nesting osprey population decline in recent decades.

The Chesapeake Bay Foundation (CBF) cites prey scarcity as the main factor, pointing the finger at Omega Protein’s annual 100 million pound-plus menhaden harvests.

Omega Protein denies claims it impacted osprey populations, saying it has cooperated with menhaden stock assessments and monitoring for decades.

Read the full article at WBOC

USGS Challenges Simple Narrative Linking Menhaden to Osprey Decline

May 5, 2025 — The following was released by the Menhaden Fisheries Coalition:

A letter from the U.S. Geological Survey (USGS) sent last week to the House Natural Resources Committee indicates multiple environmental stressors—not just prey availability—are responsible for recent osprey reproduction issues in the Chesapeake Bay. The USGS’ conclusions challenge narratives pushed by menhaden fishery opponents, including a widely publicized study by Dr. Bryan Watts of the Center for Conservation Biology, which linked a decline in osprey reproduction in Virginia’s Mobjack Bay to reduced availability of menhaden.

Menhaden increase in osprey diets is statistically insignificant

Specifically, the USGS finds that the Watts et al. (2024) study did not demonstrate a biologically significant change in the proportion of menhaden in the osprey diet over time. The agency also noted that menhaden made up a slightly higher portion of the diet in 2021 compared to 2006–07, although the difference is statistically insignificant. “Although the proportion of Menhaden as a percentage of total diet in 2021 is numerically larger than the 2006–07 value, the two values are bounded by overlapping error bars, and are thus not different in a biologically meaningful way,” the letter stated.

“The amount of food delivered to young in a nest can be influenced by many factors, including prey abundance, access to prey, … increased predation risk, parental condition, brood size, and adverse weather conditions,” said the USGS letter, which was delivered on May 2. “Ecological systems such as this are complex and occur at large scales that make it difficult and sometimes not possible to measure and accurately estimate the influence of all contributing factors.”

Chesapeake osprey trends also seen around the country

Following bird conservation measures including the banning of DDT, the Atlantic Coast osprey population increased by nearly 600% between 1966 and 2022. In the Chesapeake Bay, it has increased by about 1800% since 1960. While scientists have observed a leveling off of osprey populations between 2012 and 2022, populations remain high by historical standards. Furthermore, the USGS reports that this trend has been observed in numerous other locations including Florida, South Carolina, North Carolina, and Delaware, as well as the Pacific Coast, raising serious questions about any impact from the menhaden fishery since there is no menhaden fishery in those locations.

Overfished Striped Bass also an important food source for osprey

The USGS also identifies striped bass as an important food source for osprey in parts of the Chesapeake Bay and notes that the status of this stock may influence osprey reproduction. “Preliminary observations made by USGS scientists during a 2024 Osprey nesting study in the vicinity of the Choptank River suggest Menhaden and Striped Bass may be the primary prey type there,” the letter states. It further explains that “the principal contributing factor to poor breeding performance was loss of young due to starvation,” likely caused by “limited prey capture and/or prey delivery to nests.” Additionally, the letter notes that “the USGS has included Striped Bass among the list of prey species captured and consumed by Osprey at some Chesapeake study sites,” and concludes that “many of the factors that affect the status of the Striped Bass stock in the Chesapeake could also have direct or indirect effects on Osprey reproduction.”

The Atlantic States Marine Fisheries Commission (ASMFC) has found that Atlantic striped bass are currently overfished, with spawning stock biomass below the sustainable threshold as of the most recent assessment. Over the past decade, recreational fishing—particularly in the Chesapeake Bay—has been the primary driver of striped bass mortality, accounting for the vast majority of total removals, including substantial losses from catch-and-release mortality¹. The ASMFC has repeatedly cited recreational release mortality as a major factor in the species’ decline² and has responded with new management measures aimed at rebuilding the stock by 2029³.Conversely, the Atlantic menhaden fishery has repeatedly been found to be healthy and sustainably managed. The most recent stock assessment by the Atlantic States Marine Fisheries Commission in 2022 found menhaden is not overfished and overfishing is not occurring. The fishery has been certified sustainable by the Marine Stewardship Council, the gold standard for seafood sustainability, since 2019.

Osprey nesting sites in the Chesapeake are now at a surplus

The USGS scientists reported that the number of breeding pairs in the Chesapeake Bay increased from approximately 1,450 pairs in 1973 to around 10,000 pairs in 2020—an increase of nearly 600 percent. “All estimates indicate that the density of breeding pairs of Osprey in the Chesapeake has grown substantially since the 1970s,” the letter states. It also notes that “there are many natural structures, duck blinds, and manmade platforms suitable for nesting Osprey in the Chesapeake,” and that “Osprey nesting sites in the Chesapeake are now at a surplus and unused platforms are frequently being taken over by Canada Geese.” While the letter does not conclude that the population has exceeded environmental limits, it acknowledges that “as a natural population regulation process,” higher osprey densities increase competition for limited resources such as food and nesting sites, and that “growth usually continues until the population reaches the maximum population size the environment can support.”

VIMS also found no clear relationship with menhaden

Last fall, scientists from the Virginia Institute of Marine Science (VIMS) also found that the Watts study did not “establish a clear relationship with menhaden abundance and availability.” Both the original Watts study⁴ and the VIMS rebuttal⁵ were published in the journal Frontiers in Marine Science.

The USGS findings make clear that osprey reproduction is shaped by a wide array of environmental factors—and that no single fishery can shoulder the blame. The letter shows that blaming the menhaden fishery for complex ecological trends in osprey populations oversimplifies the science and misleads the public. Moreover, the overfished status of striped bass—driven largely by recreational fishing—may also be a contributing factor.

Footnotes

¹ Atlantic States Marine Fisheries Commission. Atlantic Striped Bass Stock Assessment Update. October 2022.

² Atlantic States Marine Fisheries Commission. Amendment 7 to the Atlantic Striped Bass Interstate Fishery Management Plan. May 2022.

³ Atlantic States Marine Fisheries Commission. Addendum II to Amendment 7. January 2024.

⁴ Watts Bryan D. , Stinson Christine H. , McLean Peter K. , Glass K. Andrew , Academia Michael H. , Byrd Mitchell A. (2023). Prey provisioning and diet of Osprey in lower Chesapeake Bay: A comparative study. Frontiers in Marine Science.
https://www.frontiersin.org/articles/10.3389/fmars.2023.1284462/full

⁵ Latour Robert J. , Gartland James , Ralph Gina M. (2024). Commentary: Prey provisioning and diet of Osprey in lower Chesapeake Bay: A comparative study. Frontiers in Marine Science.
https://www.frontiersin.org/articles/10.3389/fmars.2024.1416687/full

Osprey troubles not tied to menhaden, some fisheries scientists say

December 13, 2024 — A widely publicized study pointing to a shortage of Atlantic menhaden as the cause of osprey nest failures in the Chesapeake Bay has come under fire from a trio of Virginia fisheries scientists.

The study, published in January by researchers with the College of William & Mary’s Center for Conservation Biology, linked a drastic decline in osprey reproduction in Virginia’s Mobjack Bay with a drop in the availability of menhaden, the migratory fish that once made up the bulk of the birds’ diet. They said ospreys are having fewer young and more chicks are dying in the nest for lack of food than in decades past. They suggested that the commercial menhaden harvest be limited to sustain ospreys, also known as fish hawks.

That research report, written by center director Bryan Watts and five co-authors, gave credence to complaints by conservationists and sports anglers about large-scale commercial menhaden harvests in the Bay. Those groups have long contended that a Virginia-based fishing fleet operated by Omega Protein has been depleting menhaden stocks in the Chesapeake, depriving Atlantic striped bass and other fish of a vital source of forage.

Read the full article at the Bay Journal