ntifying Coopers and Sharp-shinned hawks in your yard

BIRD COLUMN FOR JANUARY 23, 2005


By Benjamin P. Burtt

TOPIC: Identifying Coopers and Sharp-shinned hawks in your yard.
Announcement: The February Feeder Survey starts Sunday February 6

INTRODUCTION
This column contains all of the material that appeared in the Bird Column in the Post Standard in Syracuse on the above date.


However, this web version contains additional information and additional photographs for the reader who is interested in learning more about how to identify individual birds of these very similar species.


Dear Mr. Burtt:
I am sending you a picture I took of a hawk in my backyard on October 24. We think it is a Coopers or a sharp-shinned hawk. It seemed to be bigger than a crow. Can you help us identify it?
-Mike Reissig, Liverpool.

Figure 1 Courtesy of Mike Reissig

Dear Mike:
You are correct that the bird is either a Coopers or a sharp-shinned hawk. The markings on your bird will fit either species. We can also say that it is an adult bird as will be clear in the discussion below.

So how can we determine which species it is?

These hawks belong to the Accipiter Family that are referred to as the Bird Hawks because they feed mostly on birds. There is a third member of the family, the Northern Goshawk which is larger and the adult has a somewhat different appearance. In identifying the Coopers and sharp-shin we will use the way the birds are marked, the size, the shape of the bird and the shape of the end of the tail. Lets take those up in turn.

SIZE
The painting in Figure 2 below shows the adults of both species. Note that the sharp-shinned hawk is smaller on the average than is the Coopers. Unfortunately, when we see a bird alone, it is difficult to tell how big it is. We need to compare its size to the size of another bird that we know. If you would measure the piece of drift wood the bird is perched on in your photograph, we can compare the size of the bird in the picture to the piece of wood and make that comparison.

Figure 2 Courtesy of Julie Zickefoose:

A sharp-shinned hawk is shown on the left. The Coopers hawk is on the right. Note the squared off end of the sharpie’s tail and the rounded end of the Coopers. The horizontal lines on the breast show that these are adults. Immature birds have brownish lines running up and down. This painting by Julie Zickefoose is from the forthcoming book, “Identify Yourself: The Top Birding Identification Challenges” by Bill Thompson, Editor of Bird Watchers Digest

Here are some measurements that would help us use size to identify the hawks. If you measure the distance from the tip of the beak to the tip of the tail of sharp-shins, the specimens range from 10 to 14 inches. The same measurements on a Coopers hawk are 14 to 20 inches. So their sizes overlap.

Complicating the use of size is that among hawks and owls, the female is larger than the male. A female sharp-shinned hawk can be the same size as a male Coopers hawk.

If you could measure the bird and the length is clearly less than 14 inches it is a sharp-shin and if it is greater than 14 it is a Coopers. If it was just 14 inches you could not be sure based on size alone.

In your message you said that the bird was about the size of a crow or even larger. Since the crow can be 17 to 20 inches, that would tend to rule out a sharp-shin.

The shape of the bird
The Coopers has a slightly larger head in proportion to its body and a somewhat longer neck. These are hard to judge for the bird can stretch its head up or “hunch” down a bit. On the basis of the body shape I tend to think it is a Coopers.

The tail
The best “field mark” when the birds are perched, as in the painting, is the shape of the end of the tail. Note that it is rounded on the Coopers and straight across on the sharp-shinned.

You can see this if the bird is relaxed and the tail feathers are not fanned out. Unfortunately, in the photograph you sent, the tip of the tail is concealed by a branch.

The plumage of adults and juveniles
The birds shown in Figure 2 above, are adults. They have the rusty barring ( horizontal lines) across the chest. The back and wings are a bluish gray.

Now, lets now look at Figure 3 , here are the immature birds also painted by Julie Zickafoose. This is how they look during their first year. The wings and back are brown and these birds have a streaked breast, that is the lines run up and down.
Figure 3 Courtesy of Julie Zickefoose

It is common usage in field guides when describing lines on a birds breast to use the word “barring” when the lines run left and right and to use “streaks” when the lines run up and down. ( My dictionary does not mention this use of the words. Streaks and bars seam to mean much the same thing in it.)

From the general body shape, the breast markings and your estimate of size, I would vote for an adult Coopers hawk. If we could see that the end of the tail is rounded, we would be certain.

During their second year the Accipiters look much like the adults, but it may take an additional year before they get the full adult plumage.

Another Hawk Identification Question

Here is a photograph taken by Carolyn Pyle of Freeville. Jim and Carolyn asked if I could help them identify the bird.

Figure 4 Courtesy of Carolyn Pyle

This photograph taken from the rear shows a brown back. In this case we know exactly how big the bird is. In discussing the bird over the telephone, I asked whether the bird was actually perching on that wire fence. Assuring me that it was indeed perched there, the next question was, what are the dimensions of the openings in the mesh? It had a mesh 2 inches wide and 4 inches high. The bird from top to bottom therefore is about three mesh openings high, or about 12 inches.

That makes it too small to be a Coopers hawk, but is quite correct for the sharp-shinned hawk. The brown color suggests a first year bird. But what are those white spots on the wings?

I have not seen very many sharp-shinned hawks in the wild so telephoned Dr. Kevin McGowan of the Cornell Laboratory of Ornithology. When I described it to him he said that such spotting on the wings is common on the immature birds. Later the Pyles sent him a copy of the photo and he confirmed its identity as an immature sharp-shinned hawk.

After all this, I searched my field guides for a picture of the back of a juvenile sharp-shin. I finally found a photograph in Kenn Kaufman’s “Birds of North America” on page 117. It is almost a duplicate of Carolyn Pyles photograph. There was no image in Peterson’s latest Field Guide nor in The Sibley Guide to Birds or the Stokes Guide.

So, when you see a hawk looking over the birds in your yard, it will probably be a sharp-shinned or Coopers hawk. It appears there because it is hungry too. You may have mixed feelings about it feeding on one of “your” chickadees, but it gives you an opportunity to see a relatively rare bird in your yard.

Protecting your feeder from hawks

You may wish to minimize the number of your birds that the hawk captures. First, it is wise to have shelter nearby. This can be a hiding place, such as a dense evergreen or a big brush pile within 6 to 10 feet of the feeders.

Since it is the activity of many birds near your feeder that gets the hawks attention, you can stop feeding birds for 3 or 4 days. After the hawk has gone elsewhere, put out the food again and the hawk will probably have found another place to hunt.

Results of the December Feeder Survey

BIRD COLUMN FOR JANUARY 9, 2005

By Benjamin P. Burtt

TOPIC: The Results of the December 2004 Feeder Survey

INTRODUCTION

This column is divided into two sections

Section 1 contains a summary of the results of the December Feeder Survey as it appeared in Stars Magazine of the Post Standard in Syracuse on the above date.

Section 2 contains all the results with more details such as the complete list of species and their numbers, a discussion of those species that were abundant, those scarce, the very rare species listed and those that show a population trend through this season so far.

SECTION 1: THIS IS A COPY OF THE COLUMN THAT APPEARED IN THE POST STANDARD ON JANUARY 9, 2005

What birds are showing up at feeders this winter? The table below shows a list of the birds reported on the December Feeder Survey around the average home in Central New York. The first column shows the percent of the feeders that had each species. For example, 98% of the reports listed chickadee. On the average the observers had 5 chickadees in November and in December. This table is based on the results of the Feeder Survey for the first week of December. You can compare what you are seeing with these December Feeder Survey Results.




















































Percent of feeders

species

Number per report

November

December

98

chickadee

5

5

87

junco

4

5

87

Crow

16

50

84

White-breasted nuthatch

2

2

84

Mourning dove

9

6

84

Downy woodpecker

2

1

81

Blue jay

4

4

77

Goldfinch

14

10

74

Cardinal

2

4

66

Titmouse

2

2

62

House finch

3

7

53

Canada goose

120

123

48

House sparrow

15

13

25

Tree sparrow (Nov.)

3

47

Tree sparrow )Dec.)

3




You may wonder about the tree sparrow entries. The average per feeder was 3 in November and the same in December. This suggests that there was no change. However, although people had only 3, there were a lot more people listing it. 25% of the feeders had them in November and they were reported on 47% of the feeders in December. Thus a lot more people had the bird in December so the total number reported in December was higher. They are still migrating south to our area and See SECTION 2 below where they are discussed again.

How was this information obtained? Readers counted the birds in their yard several times each day during the first week of December. At the end of the week, they sent me a list showing for each species the largest number they saw at any one time during that week. We know that there were at least that many birds of that species near their home.

There were 65 species reported altogether, but most people had about 14. The number of birds listed on a typical report for the first week of December, 2004 is shown in the table above. The results for the previous month are shown for comparison. These are in order of the birds most often reported ( i.e. the percent of the feeders that have the bird, which is the first column of numbers). The chickadee is at the top of the list since 98% of the reports listed it. Lots of crows and geese were seen, but they were not at feeders
Numbers higherWe had twice as many cardinals in December as in November. It has been ten years since there were as many cardinals reported in December. Crow numbers were up since November. More hairy woodpeckers were tallied than in the past.



Courtesy of Houghton Mifflin Co.




CAPTION: Record numbers of cardinals are showing up at feeders in Central NY this winter. Females are brown with a tinge of red in the wings and tail. First year birds are like the adults now, but not quite so brilliant. This painting is from Peterson’s “Field Guide to the Birds of Eastern and Central North America”, fifth edition . (Courtesy of the Houghton Mifflin Co. )







Numbers lower



Red-wings and grackles are low this year and the house finch population has been going down for the past three years. This winter there has been no southward migration of evening grosbeaks, redpolls or siskins.

SECTION 2

Here are further details of the December Feeder Survey that did not appear in the newspaper.

Skipping geese, starlings, gulls and crows, the most abundant bird right at the feeders was the goldfinch. In the past on the average, if people had goldfinches, they had about 5 at their feeder. This year they had 10. In Canton, John and Marilyn Ross had a flock of 76!

In the list of birds by number, after the goldfinch came the mourning dove, house sparrow, chickadee, junco and house finch.

Tree sparrows breed far north beyond the limit of the trees. Over the years, the feeder survey shows that a few leave their summer home in October and show up here. The numbers increase in November and this year the December tally was twice what it was in November. So they were following their customary schedule! Even more will be here next month. Thus they migrate over a period of several months.

In some winters northern finches migrate south into New York for the winter months. These include evening and pine grosbeaks, crossbills, redpolls and pine siskins. This time there were only seven reports of siskins and two for the redpoll. The only person to see evening grosbeaks was Pete Biesemeyer of Malone. He had 15. So those birds apparently have enough food in the north and we probably won’t see very many this winter.

THE SHORT LISTS

Short lists are just as important to a feeder survey as are the longer lists. The shortest one this time came from Norma Griffin’s fourth grade class at the New Haven Elementary School. They reported 7 mourning doves and 7 goldfinches.

Listing 5 species was Mrs. William Woernley of Homer. There were 7 on Eugenia Fish’s list from Cortland. Tallying 8 species were Niles Brown of Tully and Marsha Smith of Dryden.

There were 9 species tallied by Mary Berkman in Camillus. In the same town Helen Clark also listed nine.

THE LONG LISTS

There were 32 species on Linda Quackenbush’s list from Waterloo. Ken Smith of Freeville tallied 28. Listing 27 was Ken Zoller of West Winfield. Kathy and Scott Trefz listed 25 in Perryville. At Whitney Point, Steve and Dorothy Hanzlik listed 23. Listing 22 were John Hanyak in Marcellus., Bob Asanoma in Liverpool and Estelle Hahn in Dewitt.

Tallying 21 each were Lawrence Abrahamson in Marcellus, Dave Pardee in Brewerton, John and Elizabeth Wallace in Baldwinsville and Matt Young of DeRuyter. The average report included 14 species.

LIST OF RARITIES

There was only a single report of each of the following 16 species. The number seen is first. It is followed by the species name and then the the name of the observer and the town where the birds were seen.
1 kestrel, Lawrence Abrahamson, Marcellus.
3 Redpolls and 15 evening grosbeaks, Pete Biesemayer, Malone.
1 black Duck, Niles Brown, Tully
5 Goldeneyes, Morgan Cooper, Skaneateles Lake.
1 loon, Lawrence Daley, Cazenovia
50 lesser scaup, Sandy Pond, Don, no last name given
1 screech owl, Estelle Hahn, Dewitt
1 Horned owl, Ken Smith, Freeville.
1 Field sparrow, 1 northern shrike, Kathy and Scott Trefz, Perryville.
1 rough-legged hawk, 1 rusty blackbird, Matt Young, DeRuyter.
11 blue geese, 3 bufflehead, Ken Zoller, West Winfield

The Entire ListBelow is the list of all species reported. The first figure for a species, is the total number of them spotted on 100 reports and the second figure, the one enclosed in parentheses, is the number of reports that list the species.

If you divide the number of birds by the number of reports that listed the species, you get the average number visiting a feeder. This is how I calculated the numbers in the Table above in SECTION 1. For example, for the chickadee divide 524 by 98 and you obtain 5.3 which rounds off to 5 chickadees on the average feeder. You can make the same calculation for any other species that interests you.

Loon 1 (1); great blue heron 2 (2); snow goose 325 (2); blue goose 11 (1); Canada goose 6,537 (53).

Ducks: black 1 (1); mallard 105 (8); lesser scaup 50 (1); goldeneye 5 (1); bufflehead 3 (1); hooded merganser 9 (2); common merganser 11 (3).

Hawks: sharp-shinned 6 (6); Cooper’s 18 (17); red-tailed 27 (23); rough-legged 1 (1); kestrel 1 (1).

Pheasant 6 (6); ruffed grouse 7 (4); turkey 165 (12).

Gulls: ring-billed 149 (15); herring 37 (4); rock dove 273 (18); mourning dove 731 (84); screech owl 1 (1); horned owl 1 (1).

Woodpeckers: red-bellied 44 (38); downy 177 (84); hairy 84 (56); flicker 6 (4); pileated 5 (5).

Blue jay 297 (81); crow 2,004 (87); raven 5 (3); chickadee 524 (98); titmouse 143 (66); red-breasted nuthatch 45 (36); white-breasted nuthatch 132 (84); brown creeper 5 (5); Carolina wren 4 (4); golden crowned kinglet 1 (1).

Bluebird 9 (3); robin 66 (12); mockingbird 3 (3); cedar waxwing 156 (7); northern shrike 1 (1); starling 1,076 (33); cardinal 274 (74).

Sparrows: tree 164 (47); chipping 1 (1); field 1 (1); song 7 (4); white-throated 69 (29); white-crowned 7 (4); junco 453 (87).

Red-winged blackbird 9 (3); rusty blackbird 1 (1); grackle 5 (3); cowbird 41 (9).

Purple finch 30 (10); house finch 452 (62); redpoll 3 (2); siskin 15 (7); goldfinch 741 (77); evening grosbeak 15 (1); house sparrow 602 (47).

The next feeder survey starts Sunday, February 6