AHHerald Search

osprey landingDo you feel it? Even if it’s been a mild winter, spring is underway in the northern hemisphere. The first full day of spring, a season normally full of hope and renewal, arrived on Friday, March 20. 

Spring peepers and wood frogs are calling for a mate, flowers are blooming, crows are nesting, songbirds are singing, and river herring are migrating from the Atlantic Ocean to warmer coastal waters. All life is beginning to stir, except of course for people. Across New Jersey and the rest of the country, many people have begun adjusting to a life of home-bound isolation, an effort to radically reduce human-to-human contact and slow the spread of the coronavirus.

Every continent has suffered with the virus except Antarctica. Work and school for many people are now being done at home, and people are being asked to stay at least six feet from each other while restrictions on movement are tightened on daily activities. We are suddenly grappling with a new way of life to protect the health and safety of people amid a pandemic. People are shutting themselves off from each other while worrying about personal health, paychecks and what a post-pandemic future looks like. It’s a uniquely historical and yet stressful and frightening time.

A few people are trying to find peace of mind by paring back. Using this opportunity to enjoy a simple life and rediscovering the joys of home life.  Simpler pleasures which can be done alone, or with a close family member or friend.  For some it’s a walk around the neighborhood or in a local park, riding a bike, birdwatching, board games, gardening, cooking, baking, or another positive, personal activity that provides a higher purpose than just playing video games or watching movies all day.

osprey at rest

For me, as president of Save Coastal Wildlife nonprofit, that simple pleasure is observing the return of ospreys to the Jersey Shore. Just like clockwork, ospreys (Pandion haliaetus), a species listed as threatened in New Jersey under the Endangered and Nongame Species Conservation Act of 1973, return every spring from overwintering sites in the tropics to watery areas up north, including rivers, lakes, and the coast, to begin another busy breeding season raising a feathered family. Because of their long breeding cycle, ospreys are among the first birds to migrate north for the season.

The reappearance of ospreys every spring is one of the great natural wonders to watch for along the Jersey Shore. It’s a true sign of spring. The fun usually begins after the first of March when wildlife watchers and birders from all over the state try to spot the first osprey of the season. People are out and about in search of the bird from High Point down to Cape May.

Ospreys are found on all continents except Antarctica, and always located near water. Depending on where you go, people may call them sea hawks, river hawks or fish hawks. Ospreys are large fish-eating raptors ranging in size from 20-24 inches (50-60 centimeters) long with a wingspan of 5 to 5 ½ (1.5-1.7 meters) feet. They have dense dark brown-and-white wings, a large hooked beak and prominent large yellow eyes in adults, which provide sharpened eyesight at three to five times the distance that humans can see. An osprey is able to spot a fish about two hundred feet away. The bird’s most prominent feature, though, is the black band of feathers that span from its eyes and around its head resembling a bandit’s mask or the mask worn by that iconic “masked man” known as the Lone Ranger, which is remarkable because ospreys always migrate and forage for food as individuals, not in flocks.

Odds are pretty good you have seen this bird around the Jersey Shore during spring, summer or fall. An osprey’s nest tends to be a gigantic pile of sticks and branches haphazardly assembled atop a 20-foot tall artificial nesting platform, a buoy, or some other structure near or in the water. You may not have realized that you have spotted an osprey atop a nest or in flight. A quick glance of this bird may appear somewhat like seeing a large gull.

But ospreys are no gull. They are a distinct type of hawk and a superb angler. Most avian field guides indicate that 99 percent of an osprey’s diet consists of live fish, including menhaden or bunker, flounder and bluefish. It's the only raptor that relies so much on fishing for a living. With long legs that are largely bare of feathers, strong needle sharped curved talons, and a special reversible outer toe that swings back to help hold a fish, ospreys have evolved over time to dive into the water from heights of up to 100 feet to catch fish like no other hawk. While many other birds of prey hunt for birds, mammals, or any live land animal, or even the carcasses of already-dead animals, ospreys go where few hawks dare – into the water to fish for their food. This is why the osprey is the only member of its family, Pandionidae, there is no other bird like an osprey.

According to the Cornell Lab of Ornithology, ospreys can catch a fish at least one in every four dives, with success rates sometimes as high as 70 percent. The average time the bird spends searching for a fish before making a catch is about 12 minutes. A much better success rate than most weekend warriors along the Jersey Shore that try their luck catching a fish with rod and reel.

In fact, ospreys are so talented at catching a fish that even American bald eagles will use this bird to get food. A hungry eagle will wait around for an osprey to make a catch then attack the unwary bird causing an osprey to drop its fish. The robber eagle will then quickly snag the fish before it splashes into the water. As Benjamin Franklin declared in his writings of 1784 that bald eagles are “too lazy to fish for himself, and does not get his living honestly.” Words that are true today as they were in the 18th century.

But ospreys are more important to know than just for their fabulous fishing abilities. These fish hawks are birds of prey and predators. They play an important role in the health of an aquatic ecosystem. Ospreys help to provide balance among fish populations and keep fish populations genetically healthy by eating sick or scrawny individuals. Ospreys are also a valuable indicator species for monitoring the long-term health of an aquatic ecosystem. Birds of prey are extremely sensitive to many environmental changes in an ecosystem. Since an osprey’s diet consists almost entirely of live fish, an abundance of nesting ospreys suggests water quality and fish populations are improving to support many hungry beaks and gizzards.

For the past dozen or more years, during March I have celebrated the return of spring to the Jersey Shore by counting ospreys at their nesting sites along the edge of an estuary, usually near my home beside Sandy Hook Bay and Raritan Bay. I typically get up early on weekends to travel from one end of the bay to another to discover active nests and collect data along the way. My first look determines how many pairs have returned to nest and to which platforms. The 2019 New Jersey Osprey Project Report tells us that the Raritan Bay-Sandy Hook Bay area had 31 osprey nests that provided a home to 41 young.

But even before adults begin raising a family, I see ospreys as they simply appear following their return to the Jersey Shore after a long, grueling migration from South America. What I frequently find every spring are ospreys that look ragged, starved and exhausted. The birds have just completed a challenging northward marathon migration flying thousands of miles in most cases nearly nonstop into storms, high winds, and through hazardous situations.

Spring migration for ospreys is an extraordinary journey that we are just trying to understand. A 2001 journal article in The Condor by Mark S. Martell and others show that the sightings and returns from metal bands around the legs of ospreys indicate that spring migrations are quicker than fall migrations. Ospreys spend proportionally more time traveling than stopping to rest during spring migration compared to autumn, because of competition for prime nesting sites.

Nowadays we realize even more about osprey migrations thanks to ever improving technology. Miniaturized solar-powered GPS (global positioning system) trackers and newer solar-powered GSM (groupe spécial mobile) transmitters allow wildlife researchers to track movements of tagged ospreys in real time.

A scientific project in 2013 by the National Parks of New York Harbor Conservancy used a solar-powered GPS device. The project showed just how fast an osprey is capable of flying during spring migration. One osprey named Coley travelled approximately 2,600 miles over 15 days from Ciénaga Pajaral, or Bird Marsh, on the northern tip of the Republic of Colombia, situated near Panama, to reach the Jamaica Bay Wildlife Refuge in New York City. The bird traveled nearly nonstop at almost 173 miles per day. Clearly the need to breed was strong in this bird.

Spring migration is fast paced, and for good reason. Timing is everything if you want to acquire a healthy mate and a first-rate nesting site.

In May 2012 at Jamaica Bay in New York City, wildlife researchers outfitted another Osprey, Coley II, with a GPS pack. The next year Coley II was late in arriving back to Jamaica Bay. The bird left Lake Valencia in Venezuela on March 16th but didn’t arrive to Jamaica Bay in New York City until April 5th. A trip that took 20 days. When Coley II did arrive, he had to contend with another male osprey that was trying to mate with his long-standing female companion. It was an “interloper” who had arrived earlier from the tropics and tried to pair off with Coley II’s established mate and nesting platform.  

Even though ospreys generally mate for life, the birds will take on another partner when their established mate dies or disappears during spring migration. Each day that an osprey does not show up to a nesting site decreases the strength of the bond with a mate, making a single osprey more likely to accept the advances of another osprey.  Fortunately, Coley II arrived just in time to befriend his long-standing female partner and strengthen the pair bond once more. Another day or two and the outcome may have caused Coley II to locate a new mate and a new nest.

Curiously, stories of male ospreys arriving late to the nest are not uncommon. In 2015, the Squam Lakes Natural Science Center in New Hampshire tagged a male osprey Wausau, “named for the old Wausau Paper Mill that was an important part of the town of Groveton for so many years.” On March 23, 2016, Wausau flew about 150 miles north from his winter home in central Colombia and then surprisingly turned around and went back to his wintering area on the 23rd. No one is sure why, but Wausau took off again on March 28th and arrived at his nest in northern New Hampshire on April 18th. Due to this long delay, when Wausau arrived at his established nesting area, his mate from last year had already paired up with a new male. She probably thought poor Wausau had died. Fortunately, Wausau was able to successfully chase the intruder away, reclaim the nest, and begin the mating process with his female partner.

Perhaps the most famous and one of the longest tagged ospreys is Belle. This osprey was tagged on July 28, 2010 on Martha's Vineyard. The last signal was on April 26, 2017, after the radio failed. This osprey completed 6 migrations from Massachusetts to the Amazon Basin in South America, with a total distance traveled of 82,961 miles (more than three times around the globe), and a total migration distance of more 50,000 miles. Along the way, Belle survived a major hurricane and several storms; and avoided numerous threats from humans and other animals, including a hungry alligator.

Stories of spring migration for these ospreys are even more interesting when you take into consideration the long winding path the birds often fly to get to their breeding site. It’s an epic winged migration from South America to North America.

A study published by Mark S. Martell and others from a 2014 edition of the Journal of Raptor Research, shows that many of our east coast ospreys winter in South America with smaller amounts around Chesapeake Bay, in Florida or on Caribbean islands, including Cuba. As spring approaches, ospreys who winter in South America make a long-distance journey past the Gulf of Venezuela to briefly rest in either Haiti, Jamaica, or Cuba, after a long overwater crossing of between 400 and 700 miles. It’s a tiring flight that typically takes 27 to 40 hours and involves risky nighttime travel. Once across the Caribbean Sea, nearly all ospreys will cross Cuba to the Florida Keys and then northward to breeding grounds. The birds travel as much as 5,000 miles from the Amazon basin, across the Caribbean Sea and up the Atlantic Coast before they end up at their breeding site. An incredible winged migration that normally takes two to three weeks from start to finish.

osprey flightMigrating ospreys can cover thousands of miles during their spring travels, repeatedly traveling the same course year after year with little deviation. Moving across natural boundaries of rivers and tropical rainforests of the Amazon, the reefs and islands of the Caribbean Sea, the hills and valleys of Cuba, and past the largest subtropical wilderness in the United States known as Everglades National Park.

Along the way, ospreys have many dangerous issues to deal with. One major hazard is weather, especially when crossing large bodies of water. The birds can be blown off course or get caught up in a severe thunderstorm or windstorm. This event will drain fat reserves (fuel) and put an osprey at risk of being too weak to continue. Ospreys cannot land on the water to rest like a gull. If an osprey gets tired over the open water, it will drown.

According to researcher Rob Bierregaard from Drexel University, one tired osprey attempted to rest and “ended up on a ship that took it to Portugal.” Crossing large bodies of waters can be dangerous for birds of prey. “Most of the mortality is related to crossing the Caribbean Sea…. that’s when most adults disappear,” Bierregaard said.

Another major problem are people shooting ospreys. This happens when hungry ospreys try to take a fish from a private or commercial fish farm in the Dominican Republic, Haiti or Cuba. Many poor farmers do not take kindly to someone, even a bird, “stealing” a fish or their profit. According to a 2001 study by the U.S. Fish and Wildlife Service, about 14,000 ospreys are killed every year by fish farmers in several Latin American countries. Total mortality though could be higher, since at least 21 Latin American and Caribbean nations have fish farms along the birds’ migratory routes.

But shooting ospreys can take place anywhere including by people in the United States. In 2007, a Pennsylvania man pled guilty to killing an osprey with a .22-250 rifle at the Rainbow Paradise Trout Farm in Coudersport. The man, an employee at the trout farm, shot the osprey because the bird had been preying on fish.

Collisions with vehicles and powerlines are also are sources of mortalities for ospreys, especially during spring migration as the birds are in a rush to return to their nesting site. Electrocution is a threat to ospreys around powerlines, as well as oil spills in the waters of Venezuela. Both are critical sources of fatalities.

Woefully, ospreys have dealt for decades with many perils in their life. During the 1950s and 1960s, DDT (Dichlorodiphenyltrichloroethane), a colorless, tasteless, and almost odorless chemical compound used as an agricultural and household pesticide, caused the collapse of osprey populations throughout the country. The pesticide seeped into local waterways through runoff and accumulated in the tissues of marine organisms, including fish.

This bioaccumulation, the gradual accumulation of substances in an organism, of DDT seriously affected top predators, including ospreys, bald eagles and peregrines. The toxin impaired a bird’s ability to reproduce. DDT caused eggshell thinning which led to fewer and fewer young to replenish the population. 

The good news is that osprey populations have shown a gradual increase since DDT and similar toxic substances were federally banned in the United States in the 1970s, and water quality has been slowly improving since the establishment of the Clean Water Act of 1972. Various organizations and volunteers have also been building osprey nesting platforms to provide suitable nesting areas for the birds, as their coastal habitat became developed and fragmented during the demise of DDT.

According to the 2019 New Jersey Osprey Project Report, there were 669 occupied osprey nests — the most ever recorded in New Jersey – with around 95% of the population utilizing manufactured wooden nesting platforms. Of course, not all the nests were productive. Out of 669 nests, 488 were active and produced 932 young. Great news compared to having only about 50 nests in 1974 statewide. Osprey populations are on the rebound.

But as ospreys return to a nesting platform in the spring, the birds are welcomed regularly now by finding another sinister deadly manmade chemical – plastics. Adults and young are particularly at risk of becoming entangled in plastic string, bags, containers, or monofilament fishing line. The 2019 New Jersey Osprey Project Report also tells us that volunteers have started to remove trash and collect data from osprey nests. In 2019, out of 189 nests they monitored, 42% contained plastic debris. We live in a society where unfortunately plastic litter is very easy to find, and since the birds live close to humans, plastics often are found in their nests.

Ospreys have a shocking and scary spring migration. It’s not easy being an osprey in the modern world. It’s not a world they desired, but it’s a world that has developed around them. From habitat loss to poor water quality, to illegal hunting, to toxic pollutants and pesticides, to plastics, there are many threats to their survival. If we all work together to address these troubles though, these great fish hawks will have a chance to be around for future generations of birders, wildlife watchers and nature enthusiasts to enjoy every spring.

What you can do to help protect ospreys:

Avoid getting too close to nesting sites during the breeding season. Always maintain a respectful distance from wild animals. Always carry binoculars to view wildlife from afar. If an animal vocalizes when you're near, you are too close! Immediately back off.

Restore coastal and wetland habitat.

Preserve existing coastal habitat, including wetlands and dunes.

Help keep local waters clean, healthy, and safe.

Recycle used fishing Line.

Volunteer to help members of Save Coastal Wildlife install new nesting platforms at wetland sites along the Jersey Shore. Artificial nesting platforms are generally more stable and safer than the natural nesting areas (usually dead trees).  Nesting success is also commonly twice as high on artificial sites compared to natural sites.

If you don’t live near a nest, you can always watch the action online. There are many osprey nests on the web to watch. In 2019, The Conserve Wildlife Foundation of New Jersey installed a new osprey cam in Barnegat Light. The action can be seen here

http://www.conservewildlifenj.org/education/ospreycam/

To find more information about coastal wildlife, including whales, please visit the website for Save Coastal Wildlife, a wildlife conservation nonprofit organization dedicated to educating people about the preservation and protection of coastal wildlife along the Jersey Shore at www.savecoastalwildlife.org

 

joe reynolds 200Joe Reynolds