Archive for March, 2018

A friend of mine has been volunteering with the National Park Service to track the nesting activities of raptors in the Presidio in San Francisco, CA for the past twenty years. There are four species of bird of prey that nest in the park. They are Red-tailed Hawk, Red-shouldered Hawk, Cooper’s Hawk, and Great Horned Owl.

Information that has been collected include where these birds nest, how many nest in the park, when stages of nesting (breeding, egg laying, incubation, etc.) occur, how many chick fledge from each nest, etc.

This project has taken a wonderful turn this year with the installation of nest cams! My friend, and others, have been working with the Park Service to get funding to purchase and install nest live-cams on some of the active nests. One of the first such cams has now been installed on a Red-tailed Hawk nest that has been built between the branches of a Blue Gum Eucalyptus Tree. The live-stream of this nest cam can be found on YouTube HERE.

RTHA Nest Cam Capture

Male Red-tailed Hawk in the Presidio, San Francisco, CA incubating the one egg that had been laid at this point. Note thin, black barring that are restricted to near the base of the tail.

The pair of Red-tailed Hawks have laid one white, and lightly speckled egg in the nest as of 3/7/2018. The male and female can be distinguished by a few characteristics. The best is by tail pattern. The male has a few, very thin black bars on its red tail. These bars are limited to the base of the tail. The female, on the other hand, has those thin black bars on the tail that extend just about all the way down to the black subterminal band near the tail tip. Beyond these tail pattern differences, the male and female have different molt patterns on the secondary flight feathers, the male is slightly smaller than the female, and the male is banded!

RTHA Nest Cam Capture F

Female Red-tailed Hawk in the Presidio, San Francisco, CA incubating the one egg that had been laid at this point. Note the thin, black barring that extend all the way to the subterminal tail band.

I have already noticed a few interesting things after only checking in on the nest for a couple of days. One is that when the the male comes to the nest to give the female a break, he sometimes brings nesting materials to add to the nest. He does this even though the nest is complete and an egg has been laid.

So far, about 60 people have been watching the nest at any given time. I am sure that this number will go up, and it will be great to push it as high as possible, since I am also sure that the Park Service will be more inclined to install more live-cams if the public response is positive and strong. So watch the Red-tailed Hawks and see what is going on at  the nest!


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This year, 2018, I have set up a little challenge for myself. The challenge is to see 100 or more species in Yolo County each month. Now, that does not mean that the 100 species of February have to all be different species from the 100 species in January. Rather it means that the total number of species seen in each month should get to a total of 100 or more. So, if I see a Red-tailed Hawk some time in January it gets added to the January list. If I see a Red-tailed Hawk some time in February it get added to the February list.

I am hoping this will help me to notice more details as I search to find that next species for a given month, encourage me to visit more habitat types each month, and highlight the seasonal differences as species come and go from my monthly list. I am looking forward to it, and will share what I see with you as the months go by.

Below is my species list from February. It has a total of 105 species, which is exactly the same number of species I saw in January, so I made my target! This month was a really nice raptor month including 3 Ferruginous Hawks, 3 falcon species, Sharp-shinned Hawk, and Cooper’s Hawks among others. Cedar Waxwings were surprisingly hard to find, for me, this month. The most surprising misses were Say’s Phoebe and House Sparrow; two species that I specifically tried to find on a couple of occasions.

I am definitely continuing to enjoy this challenge. I am looking forward to seeing what I can find in March!

Here is my February species list.

Species – Yolo County – February
1 Snow Goose
2 Greater White-fronted Goose
3 Canada Goose
4 Wood Duck
5 Blue-winged Teal
6 Cinnamon Teal
7 Northern Shoveler
8 Gadwall
9 American Wigeon
10 Mallard
11 Northern Pintail
12 Canvasback
13 Common Goldeneye
14 Common Merganser
15 California Quail
16 Wild Turkey
17 Pied-billed Grebe
18 Double-crested Cormorant
19 American White Pelican
20 Great Blue Heron
21 Great Egret
22 Snowy Egret
23 Green Heron
24 Black-crowned Night-Heron
25 White-faced Ibis
26 Turkey Vulture
27 White-tailed Kite
28 Northern Harrier
29 Sharp-shinned Hawk
30 Cooper’s Hawk
31 Red-shouldered Hawk
32 Red-tailed Hawk
33 Ferruginous Hawk
34 Virginia Rail
35 Sora
36 Common Gallinule
37 American Coot
38 Sandhill Crane
39 Black-necked Stilt
40 American Avocet
41 Killdeer
42 Long-billed Dowitcher
43 Wilson’s Snipe
44 Greater Yellowlegs
45 Ring-billed Gull
46 California Gull
47 Herring Gull
48 Rock Pigeon
49 Eurasian Collared-Dove
50 Mourning Dove
51 Barn Owl
52 Great Horned Owl
53 White-throated Swift
54 Anna’s Hummingbird
55 Belted Kingfisher
56 Nuttall’s Woodpecker
57 Northern Flicker
58 American Kestrel
59 Merlin
60 Peregrine Falcon
61 Black Phoebe
62 Loggerhead Shrike
63 California Scrub-Jay
64 Yellow-billed Magpie
65 American Crow
66 Common Raven
67 Tree Swallow
68 Barn Swallow
69 Oak Titmouse
70 Bushtit
71 White-breasted Nuthatch
72 House Wren
73 Marsh Wren
74 Bewick’s Wren
75 Golden-crowned Kinglet
76 Ruby-crowned Kinglet
77 Wrentit
78 Hermit Thrush
79 American Robin
80 Northern Mockingbird
81 European Starling
82 American Pipit
83 Cedar Waxwing
84 Orange-crowned Warbler
85 Common Yellowthroat
86 Yellow-rumped Warbler
87 Fox Sparrow
88 Dark-eyed Junco
89 White-crowned Sparrow
90 Golden-crowned Sparrow
91 Savannah Sparrow
92 Song Sparrow
93 Lincoln’s Sparrow
94 California Towhee
95 Spotted Towhee
96 Western Meadowlark
97 Red-winged Blackbird
98 Tricolored Blackbird
99 Brown-headed Cowbird
100 Brewer’s Blackbird
101 Great-tailed Grackle
102 House Finch
103 Purple Finch
104 Lesser Goldfinch
105 American Goldfinch



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