Blog #356 Raptor Conservation Trends

Migrating adult male Osprey at Hawk Mountain, courtesy of Bill Moses. 

Earlier in 2021, millions of Americans who appreciate birds in their yards and parks  were aghast when news reports announced that about 3 billion birds had been lost over  the decade. However, these studies largely overlooked raptors. What is happening to  their populations? 

Although Bald Eagles and Peregrine Falcons have recovered from near-extinction  during the DDT era of the 1960-1970s, the status of Ospreys and other raptors have not  been well documented, primarily owing to financial constraints. Annual surveys of  breeding bird conducted across the country collect vital data on many bird species, but  most do not sample raptors sufficiently to ascertain population trends. 

Recent analyses by the Raptor Population Index Project (RPI), a partnership of Hawk  Mountain Sanctuary, Birds Canada, Hawk Migration Association of North America  (HMANA), and HawkWatch International, show declines in some migratory hawk  populations and increases in other species. The updated RPI analyses examine this 

past decade of migration counts for 26 raptor species from 76 sites stretching from  Panama to Canada. One study found that one of the most-commonly observed  migrants, the Sharp-shinned Hawk, has declined 47%. Declines in Northern Harriers,  Northern Goshawks, Rough-legged Hawk, and American Kestrels also have been  detected. HMANA also reports widespread increases in Bald Eagle as well as turkey  and black vultures. Increases in Bald Eagles may play a role in recent Osprey declines  at eastern inland sites. 

Data from the last ten years show that many raptor populations appear stable, but monitoring should continue to detect any changes. Hawk Mountain founder Rosalie  Edge said it best: “the time to protect a species is while it is still common.” 

How are Osprey Faring? 

RPI’s Ten-year Osprey Migration and Winter Trends. Note decreases around the Great Lakes. 

Migration counts of Ospreys over ten years (2009–2019) suggest mostly stable  numbers across North America with 65% of sites showing stable counts and 30%  showing a decline. In the East, patterns are similar with 60% of sites showing stable  counts in the last decade and 35% declining. Most of the Gulf sites reported stable  Osprey counts, whereas 35% of Central Region sites had increasing trends and 100%  of the West Region sites were stable (see trend map above and pie charts below). 

Pie Charts showing Regional Osprey Population Trends

Osprey declines during the past decade focus around the Eastern Great Lakes and  Appalachians and not along the Atlantic Coast or farther west. Twenty-year count trends  show similar mixed trends varying among regions. Although the highest average counts  occur at coastal sites such as Cape May, New Jersey, with 3,700 Osprey per year,  notable declines have occurred at sites such as Quaker Ridge, Connecticut, averaging  525 osprey per year with a 3.3% per-year decline in the recent decade. Many  researchers suggest the increasing population of Bald Eagles at inland lakes may be  limiting nesting sites for Osprey in inland lakes. Along coastlines, Osprey often cluster in  colonies and maybe better able to stave off competition and predation by Bald Eagles.  More research is needed to understand the reasons for the observed decline. 

The Christmas Bird Count winter survey data on resident and migrant Ospreys in  southern coastal states from Carolinas to Florida and west to Texas and to California,  Oregon, Washington. Except in Washington where Ospreys are declining, coastal regions show mostly increasing or stable 10-year trends for these populations. The  Osprey is currently listed as a species of Least Concern throughout its range by the  IUCN Red List (International Union for Conservation of Nature’s Red List of Threatened Species), as it is vulnerable to threats such as habitat loss, increasing competition with  bald eagles, bioaccumulation of heavy metals and contaminants in their food, collisions,  and entanglement. 

For more information on recent RPI results and population status updates for raptor  species, trend graphs and maps, visit the RPI website (http://www.rpi-project.org/) or  contact one of the partners. 

Eyes to the sky! 

Candace 

Candace E. Cornell 

Friends ofSaltPoint 

Lansing, NY 

Cayuga Lake Osprey Network 

NY cec222@gmail.com

EYESTOTHE SKY! 

WATCH! 

Salt PointOspreyNest Cam 

READ! 

OnOspreyTime Ospreys of Salt Point 

VISIT! 

Cayuga LakeOspreyTrail

Comments

Post a Comment

Popular posts from this blog

Blog #461 Sneak Peek at Osprey Season 2024

Image
  Orpheus (L) and Ursula at their Salt Point Nest March 26, courtesy of Cindy Sedlacek. The following is a sneak peek at what this Osprey summer will entail. Our northeastern Ospreys return to their breeding habitats just after the early spring thaw. This year’s first Osprey was seen in Cayuga Lake Basin on March 15, an early date many attribute to  the mild winter. Most nest occupants will have returned to their nests and reunited with their mates by this weekend. These returning Ospreys have just completed their 2,000–4,000-mile migrations from their wintering areas along the coasts of South America and in the wild Amazonian tropics. The range of landscapes that a cosmopolitan Osprey can experience in its lifetime is staggering. In general, the older breeding males arrive on their nests followed by their mates in a few days. After that first wave of older Ospreys arrive, unmated adults and second-year birds migrating north for the first time after spending two years in the S...
Read more

Blog #397 Halfway Mark: Three Weeks

Image
  On Osprey Time On Osprey Time just moved to blogger.com. Pardon the delay in posting.  Please bookmark! A mother feeding her 3.5-week-old offspring, courtesy of Cynthia Sedlacek.   Three and a half weeks into the nestling period, the three chicks have grown halfway to their adult size with Moana, the eldest, weighing just shy of a pound. Full-grown adult males usually weigh 2 pounds and females can be up to 4.4 pounds. Sleeping through most of the day and all night, the pile of offspring springs to life whenever their father, Orpheus, brings a fish to the nest. When awake, the nestlings waddle around the nest with their enormous feet, defecating over the nest edge, and peering over the rim at the people below. They are starting to use their wings for balance and rock forward on them to get a good stretch. When it’s mealtime, the eager chicks make their way across the nest to get fed by their mother Ursula.   Once their crops (storage organs; see second photo below...
Read more

Blog # 474 Not an Empty Nest

Image
  Ursula and two of her offspring waiting for Orpheus to arrive with food, courtesy of Cindy Sedlacek. With the fledglings flying about, the nest looks empty, and it is most of the day. However, the nest is still a noisy family meeting place for meals and a refuge for sleeping fledglings. The siblings’ days are spent practicing important survival and life skills derived from combinations of instinctive (nature) and learned (nurture) behaviors. Ursula takes it easy in the shade of the cottonwoods as she is no longer needed by her family. She’s begun feeding herself to make up for the weight she lost over the breeding season and visits the nest at mealtime happy to nibble at a fish. After she has regained her strength, she will migrate to her wintering spot somewhere in South America, dodging hurricanes along the way. At noon today, Ursula went to the nest calling for food. She was joined by fledglings O’Connor, O’Leary and O’Shea in an ear-piercing chorus of begging that probably tr...
Read more