Black-crowned Night Heron
The nagging mystery remained until this spring when, at about 10 p.m. in the evening, I came upon two of them perched upon a club dock that was well illuminated by floodlights. They were less than 50 feet away and simply flew to another part of the dock as I approached for a closer look. This time I made better mental notes. They were white, had a black cap and had distinct black sections on their folded, grayish wings.
Upon consulting Peterson, the only match I could vaguely make was with a "Black-crowned night heron" however the illustration shows a bird in a "crouched down" stance, while the birds I saw were standing with their necks somewhat outstretched.
At least with this clue, I then surfed the 'net for more pictures of the Night Heron and happened upon the "Younghusband Farm" site in Cook County, Illinois, just north-west of Chicago. Here was a picture of a bird that correlated very well with the birds I had seen! (the picture happens to be Doug Rodda's, below).
Evidently the bird can appear in one of two stances- the "stretched out look" and what I call the "Penguin look" as shown in the two following photographs. Just recently on this July 30, at about 10 p.m., I was fortunate to observe one of these herons standing very motionless in the water on a rocky shoreline, again in the "stretched-out stance,
 Black-crowned Night Heron |
 Black-crowned Night Heron |
Note, however, that my observations were in a complete urban environment-no marshes or wetlands in the immediate vicinity. Oddly enough, over the years that I have spent at the Toronto waterfront (sailing), I had not noticed these birds before! They are altogether different from the ubiquitous gulls and terns that we take for granted (It could be that I just did not pay attention).
This is an interesting bird to be on the lookout for anywhere and anytime in the Spring, Summer or Fall along the lower Great Lakes waterfronts and the St. Lawrence valley. Except for its yellow-crowned more southerly counterpart, it's the only night feeding waterbird in North America that I am aware of.
Although I have provided a number of reference links to detailed information about this bird, here are a few salient points gleaned from that literature:
1. It is a night feeder, somewhat inactive during the day.
2. It may be found perched or roosting in trees.
3. It will nest on the ground or in trees, whatever its preference.
4. Its diet ranges from minnows to mice.
5. It can be found in urban environments (viz. New York City, for example).
6. In the breeding season it has Two long, white, filamentous plumes extending from the back of its head.
7. The literature indicates that the bird is found generally from southern Canada, through the USA and down into Argentina.
8. The young heron appears completely different as shown in the photo below. It begins to resemble the adult after two years but only attains full adult appearance during third year.
Black-crowned Night-heron, immature
copyright © T.Douglas Rodda.
(sawwhet@ix.netcom.com)
BREEDING RANGE AND MIGRATION
This heron is widespread with summer breeding ranges in North and South America, Africa, and Eurasia. As of a 1990 study there were two large breeding ranges in North America. The northern limit of the Canadian part of the breeding range includes the lower halves of Alberta, Saskatchewan, Manitoba, then parts of the lower Great lakes and then roughly up the St. Lawrence valley.
The winter range covers southern Oregon, southern Nevada, central New Mexico, southern Texas, the Gulf Coast, southern New England, through to Central America and the Caribbean islands and it seems that adult birds travel further than the younger birds. Of birds banded in Ontario and Quebec, winter (November through March) adult birds were recovered in the Bahamas, Cuba, and the Dominican Republic while "juveniles" were only recovered in the eastern area of North America.
Another part of this same study indicated that the returning herons do have a noticeable tendency to return to the area of their birth.
NESTING SITES - TORONTO, ONTARIO AREA
The locales of my observations of this bird are too busy with people, cars and boats during the day and are obviously not nesting sites. These are possible feeding areas during the quiet nights and I expect that what I saw last Fall (October, '97), during the day, was a group preparing to migrate.
Around Toronto, the major nesting site for this bird is an area called "The Leslie Street Spit (or Tommy Thompson Park)". There is a relatively large number of Night Herons actively nesting at the Spit right now and intrusion by visitors is discouraged. The number of Black-crowned Night-Heron nests is reported to be between 800 and 1000 making Tommy Thompson Park the largest known colony in Ontario.
The Leslie Street Spit, or just "The Spit", is an ongoing landfill site that has managed to combine landfill activities along with a segregated wildlife refuge. The spit juts out in a partial crescent into Lake Ontario adjacent to Toronto Harbour. The Spit has a long history, having been started in 1959 for the purpose of accumulating construction rubble and material dredged up from the nearby shipping channels. Landfill operations are conducted on weekdays with the refuge section being open to the public on weekends and holidays only. A link to the Tommy Thompson Park website is provided in the references below. The website is quite extensive, with numerous photographs and it describes the whole (continuing) evolution of the Park.
NESTING SITE COMPETITION - THE DOUBLE-CRESTED CORMORANT
The Black-crowned Night Heron has to compete with all of the incumbent shore birds for nesting sites and materials. Fortunately it is capable of nesting in trees and bushes if the conditions are right and if all populations are relatively stable.
This competition becomes more severe when another species shows up on the scene and explodes in population. This is the case with the Double-crested Cormorant. The population of these birds around Toronto has greatly increased in the last few years. Numerous large flocks of them in flight are a common sight now.
I have been unable to find Internet information about the effect that cormorants have had upon the Spit however on a recent visit I witnessed an extremely large population of cormorants - probably into the thousands - and this many birds cannot fail to have a negative impact on the other birds.
The nearby city of Hamilton's McMaster University has studied the Cormorants in the context of Hamilton Harbour and environs (about 40 miles west of Toronto). The information is on the Internet and is well worth reading. I have provided a link to this information in the references and it is also quite extensive.
At Hamilton, a steel mill city, a programme entitled "Ecowise" is underway. It all began in the early 1980's when the International Joint Commission (IJC) declared Hamilton Harbour to be one of 43 environmental "Areas of Concern" (AOC) in the Great Lakes Basin. The programme is involved with the rehabilitation of that area's ecosystem and mentions the nesting of Black-crowned Night Herons. I have provided links to this subject in the reference section. The material is rather extensive but an excellent example of a major effort by government, business, the community stakeholders and the general public at rehabilitating a severely damaged ecosystem.
In closing, here is a photograph of this bird by Don Baccus. It shows very clearly the plumes that extend down the birds back. One can see that it has the rather large eyes required for night vision.
Black-crowned Night-heron, Bear River NWR, Utah
Copyright © 1998, Don Baccus
(dhogaza@pacifier.com)
Acknowledgement and thanks:
Many thanks to Leslie Day, Doug Rodda and Don Baccus, for permission to use their photographs of the Herons.
Heron-NYC "The Black-crowned Night Heron at New York City, west side by Leslie Day".
Texas Black-crowned Night Heron...Texas Parks & Wildlife - Fact sheet
Rehab. Black-crowned Night Herons ("Neanderthal" and its older cousin "Mandible") in rehab. Santa Barbara Wildlife Care Network, California. check out "Bert" the Raven also.
New York City NYSite West Side - The City Naturalist.
The Farm Younghusband Farm, Cook County Illinois.
Heron Picture of Night heron perched in tree.
Bear Bear River Migratory Bird Refuge, Utah (Est. April 23, 1928).
Bear river Thumbnail Guide To Bear River National Wildlife Refuge, by Don Baccus.
The Leslie Street Spit (Tommy Thompson Park):
Toronto Map of Toronto area showing the Leslie Street Spit (Tommy Thompson Park) jutting out into the lake (bottom right hand area)
The Spit The Spit: It's an odd approach to making a 'garden'! This link became unavailable, however the author has kindly gave permission to include the article directly into this website. ("Back" to return)
Ecology. Ecology of The leslie street Spit.
Park Tommy Thompson Park.
Hamilton, Ontario (Hamilton Harbour & Cootes Paradise):
Cormorants The Rise of the Double-crested Cormorant on the Great Lakes: Winning the War Against Contaminants.
Hamilton Hamilton-Designer Islands for Caspian Terns.
Ecowise Hamilton harbour and environs.
Cootes Ecowise restoration & Cootes Paradise
Cootes2 More about Cootes Paradise
THE PHOTOGRAPHERS / NATURALISTS
Leslie Day Environmental educator; Founder and President of the 79th Street Boat Basin Flora and Fauna Society. Check out the many naturalist subjects by Leslie Day at her index.
T. Douglas Rodda. Doug's photographs appear on a number of websites, and publications such as those of the Nature Conservancy, the home page of the Darien Audubon Society, and Birder's World magazine, to mention just a few.
Doug's website provides an extensive gallery of his photographs. He also provided photographs for my page on the Killdeer