American Kestrel Nest Survey NYC
Bob got his PhD studying the NYC environment, and has done bird migration research in many parts of NYC, from Central Park to the top of the Empire State Building at night to Southeast Asia (Malaysia and Thailand dating back to 2000) and central Asia (Nepal and Israel dating back to 1999).
Bob's publication are not available for mobile. Please access the desktop site to see Bob's work..
This week we report some interesting observations, regarding food items eaten by NYC Kestrels,
Richard Lieberman and I had the opportunity to investigate several Kestrel nests on the west side (Broadway area) of Manhattan.
With this issue we are coming directly for you…and apologies in advance if we seem to be “in your face.”
Research & Publications
Beginning in the early 1980s, I became interested in raptors migrating through NYC and also those hawks/falcons that nest here. By the 1990s, along with Deborah Allen, I began studying the American Kestrel in the five boroughs. In 2008, I was awarded a $20k USD grant to study American Kestrels here in Gotham. This would be the first study of these birds in NYC, and one of the few studies of urban kestrels in North America.
To make people aware of these falcons, and receive reports about kestrels from anyone (and all neighborhoods) in NYC, we came up with a flyer, "Have you seen this bird?" - and our friends translated it into almost 20 different languages. Below, each of those flyers is available - feel free to download and distribute to anyone..
If you want the best summary of NYC Kestrel nest sites including what to look for to find a nest; how to ID male/female and young kestrels...and what we learned in our study, simply download our 2010 popular article published in "Winging It" the newsletter of the American Birding Association: "The Falcon that Nests on Broadway" - see below.
Central Park Research
NYC Kestrel Newsletters
Starting in 2008, we began publishing a free NYC Kestrel Newsletter that provided images and detailed info on the status, timing, nest site selection and ecology/behavior of American Kestrels in the five boroughs and beyond. All of the Newsletters are available for free download below. They have been organized by date and year, for each year 2008-2011 inclusive. All issues primarily cover the spring (nesting) period, February through July. Again, if you hover your mouse over a particular issue in a particular year, you can see what date that Newsletter was published - each issue covered the previous (approx.) week to ten days.
In all, we published 50+ issues of the NYC Kestrel Newsletter; the years 2009-2010 were the heyday of the Newsletter when we provided info/photos on most of the estimated 60+ pairs of kestrels nesting in NYC...primarily in Manhattan, as well as parts of Brooklyn, the Bronx and Queens. American Kestrels are a very rare nesting species on Staten Island - you will have to read the Newsletters (or the 'Winging It' article above) to find out why Staten Island is not preferred kestrel nesting habitat.
Since the late 1990s, I have worked on several research projects in Central Park, including the reintroduction of the Eastern Screech Owl (1996-2002); Raptor Migration over Central Park (1996-2001); the flora of Central Park (2006-07); Nesting Ruby-throated Hummingbird (2014); and nesting Peregrine Falcons along Central Park West (2014-2017). Below you will find several scientific and popular articles on these topics.
History/Reintroduction of the Eastern Screech-owl in Central Park and New York City, 1867–2005
Birder's World - December 2002 - Robert DeCandido and Deborah Allen
The naturally occurring historical and extant flora of Central Park, New York City, New York 1857–2007 by Robert DeCandido
First Recorded Nesting of (Archilochus colubris) in Central Park and New York County – Spring 2014
a study of the Peregrine Falcons that nest along CP West at 62nd street, and this falcon's history in Manhattan. Published in The Kingbird, March 2016; 66 (1): 13-18
New York State Conservationist, Vol. 62 (3): 2-8 (2008) - a popular article on the flora of NYC.
A scientific article that examines long-term changes in the flora of NYC from about 1860 to 2000. It was published in 2004.
The Flora of New York City
As part of my phd dissertation research, I looked at long-term changes in plant species diversity in Pelham Bay Park (PB PK) in the Bronx. I also did the same analysis of the flora of NYC examining the 1860-2000 time frame. (For example, at one time NYC had more than 30 orchid species, but by 2000, only about eight could still be found growing somewhere in the city - an (approx.) 80% decline.) Similarly, in every park in the city, wildflowers and other herbaceous species (ferns, grasses) were the most likely plants to become extirpated (locally extinct). My plant research in Central Park (2007-2008) showed the same pattern - the great loss of native wildflowers, ferns and grasses (herbaceous species). Below you can download the scientific and popular articles that show what plant species were here in the past, what is here now (including non-native plant species) - and some explanations for why changes in our flora occurred.
(New York Times) Despite miles of skyscrapers and pavement in New York City, nature has not lost its foothold, at least not yet - By CAROL KAESUK YOONAUG. 6, 2002
Recent changes in plant species diversity in urban Pelham Bay Park (Bronx) 1947–1998
The historical and extant vascular flora of Pelham Bay Park, Bronx County, New York 1947–1998
A first approximation of the historical and extant vascular flora of New York City: Implications for native plant species conservation
The historical and extant flora of Central Park with an analysis of what the park looked like in the past compared to the present...and how/why did the changes occur?
Night Migration Bird Research at
the Empire State Building
In spring and autumn 2004-2005, I was granted permission by Management of the Empire State Building (ESB) to see what effect (if any) the lights of the building had upon night migrating birds. I was given an "Empire Pass" that allowed me and up to five assistants to go up for free each evening without having to wait on any lines. My time at 1050 feet above sea level in the open air deck was one of the most exhilarating experiences of my life studying bird migration.
We made scientific discoveries right in the heart of Manhattan that no one had seen/documented before: that Peregrine Falcons regularly hunt nocturnal migrants; that Ospreys migrate at night; and that Great Egrets and other herons migrate at night. As for the lights of the building affecting bird migration: this is a complicated subject and I urge you to read the scientific articles and reports. In a nutshell: most nocturnal bird migration over NYC occurs when winds come from a westerly direction. If winds are greater than about 15-20mph (not uncommon at 1050 foot elevation), birds have little to no problem flying past the ESB. On the other hand, if winds are less than approx. 15mph, some to many birds will circle the building, particularly from about 1000 feet and up. Light can have an effect upon migrating birds at night in NYC, but a lot depends upon weather conditions.
Here in NYC, night migrant birds are in greater danger from colliding with glass in the early morning hours than becoming disoriented from the lights of the ESB. Again, this is a complicated subject (and I give slide [PowerPoint] talks on the topic), so I urge you to read what I wrote - and ask me questions. Today, with the replacement of the old style lighting arrays at the ESB, new style LED lights seem to have reduced the number of birds circling the building during spring/autumn migration.
Click on the images below to read my research.
Nocturnal bird migration From the top of the Empire State Building; - Winging It, 2007
Nocturnal Hunting By Peregrine Falcons At The Empire State Building, New York City - The Wilson Journal of Ornithology 118(1):53–58, 2006
Evidence of Nocturnal Migration by Osprey in North America and Western Europe, 2006
New York Times article about Bob and the Empire State Building, 7 October 2004
Spring 2004 Visible Night Migration of Birds at the Empire State Building - The Kingbird, 2004
Noctural Migration from the Observation Deck on New York's Empire State Building.
Birding on high in the still of the night sky at the Empire State Building - a group of New Jersey birders came to visit us.
Spring 2004 report on the nocturnal migration of Birds at the Empire State Building
Research on the Birds of New York City
Since the late 1980s I have been doing research on (and publishing about) the birds of NYC. From 1988-1991, I ran the Pelham Bay Park Hawk Watch, the first season-long raptor migration count in the five boros. Later I ran the Central Park Hawk Watch (1996-2001). I have also done research on the Eastern Screech-owls of NYC (1996-2002); the night migration of birds as seen from the Empire State Building (2004-2005); nesting Peregrine Falcons, American Kestrels, Turkey Vultures and Ruby-throated Hummingbirds of the Big Apple as well.
Click on the images below to view articles on my research of the birds of NYC.
Nocturnal Hunting By Peregrine Falcons At The Empire State Building, New York City (2006). Published in the Wilson Journal of Ornithology
First Successful Nesting of Peregrine Falcon along Central Park West, New York County, Spring 2014-15
First nesting of the Cooper's Hawk in New York City since ca. 1955; published in the Kingbird.
Evidence of Nocturnal Migration by Osprey in North America and Western Europe published in the Journal of Raptor Research
Observations on Osprey migration at Pelham Bay Park in the Bronx - published The Linnaean Newsletter, Vol. 45, No.2, 1991
Summary of the amazing 1990 season when we counted more than 15,000 raptors on migration over Pelham Bay Park, Bronx, New York, 1990
Thailand & Malaysia Research
Click on the images below to view Bob's research.
Flight identification and plumage descriptions of six Accipiter species on southbound migration at Khao Dinsor, Chumphon province, Thailand
Mass northbound migration of Blue-tailed Merops philippinus and Blue-throated M. viridis Bee-eaters in southern Thailand, spring 2007–2008
Observations on the 2009 southbound migration of three bee-eater species at Radar Hill, Thailand
(2010) Bird Hides and Water Holes: A Model Conservation Project near Kaeng Krachan National Park - Thailand - BirdingASIA 13: 57-61
Nepal Raptor Research
Click on the images below to view Bob's research.
Steppe Eagle and other raptor migration, Central Nepal, Autumn 1999 published in the Journal of Raptor Research.
The east–west migration of Steppe Eagle and other raptors in Nepal and India - BirdingASIA 2014
The identification of Black-eared vs. "Pariah" Kites in Asia published in BirdingASIA
An article in BirdingASIA about several vulture feeding stations ("restaurants") in Nepal and how to visit them.
A brief report on 2016 migration results, significant developments and plans for 2017 self-published report by Robert DeCandido PhD
A 2013 popular article about Hawk Mountain's involvement with Nepal's burgeoning raptor migration scientists.
Some additional articles about my work in NYC and beyond..