Sagebrush and Bell's (canescens) Sparrows

In case you hadn't seen Peter Pyle's writeup on distinguishing Sagebrush and (canescens) Bell's Sparrows in fresh plumage (fall/early winter; the primary period when their ranges will be overlapping), you can find it here. What is particularly useful is that the writeup contains photos of study specimens from Berkeley's Museum of Vertebrate Zoology; most of these photo sets are comparing fresh plumage, but a few are of worn plumage.

Definitive Prebasic Molt (according to the Sage Sparrow Birds of North America (BNA) account) begins in June, finishing by mid-September (whether anyone has looked at timing differences etc by subspecies, I don't know). Records of arrivals of Sagebrush Sparrows onto territories range from late February to late April. In Mono County, canescens begins nest building in early March, and the final nests started in mid-late June. Southern populations of canescens may start up earlier (I haven't seen any data on it) but I suspect will at least skew to the early side of that range. At any rate, you can see that there will be worn Sagebrush Sparrows migrating northward through canescens territories!

As a note to make things more interesting for us all, the BNA account notes that migrating flocks of "Sage Sparrows" have been found containing both (canescens) Bell's Sparrows and Sagebrush Sparrows.


Hope you find it useful, too!
Jen

Territory Mapping

Vermilion Flycatcher female on nest in screwbean mesquite

I’ve had some folks ask me about territory mapping, so I thought I’d share a bit about how the Nevada Bird Count does it (the Lower Colorado River project does it slightly differently in order to meet their particular program goals – minor variations on the same theme!).   Territory mapping (we’ll often also refer to it as area searching or spot-mapping) is my personal favorite way to get acquainted with birds of a new region or habitat, and is a fantastic way to learn the natural history of bird and plant communities.  Nothing beats point count transects for the chance to hike and explore and get a wide breadth of understanding of your birds and habitat, and their variation across the landscape – but the area searches are a great way to get depth.  Our plots are of variable size – basically, we want a plot to be big enough that we’re able to have it covered by 9:30-ish in the morning, but small enough that we’re able to have it covered well, and aren’t glossing over sections to get them done on time.  Not surprisingly, therefore, our Mojave Scrub plots are going to be a larger size than our coniferous forest or riparian plots – the former have a lot less habitat structure and fewer birds, so we’re able to cover more ground.  A 300 x 300m plot is fairly typical in streamside vegetation, where there’s a lot of structure.  We visit each plot 8-10 times; often our Mojave Scrub or sagebrush plots are able to be thoroughly mapped within 8 visits, but those extra 2 visits can make a big difference in our more complex plots!

Another area search plot, Sandy Valley

Basically, our surveyors are given an aerial photo overlain with a UTM grid, and on each visit, they will walk through the plot in a different pattern, making sure that they get within 50m of every part of the plot on each walk-through.  The different routes ensure that each part of the plot will get surveyed during the best part of the birding morning on at least one occasion, so we don’t have one location that is always surveyed at 5:30 a.m. and one location always surveyed at 9.  We walk through the plot, looking at and listening to birds, watching their behavior, and marking down their locations on our aerial photo.  Once we’ve finished our initial walk-through, somewhere between 9 and 10am, then we’ll often head back to a perplexing area to spend some more time watching, listening, and mapping.   The 2 biggest things to remember are (1) following individuals and (2) simultaneous detections.  When we find an individual, it’s useful to spend some time with it, marking down the path of that individual’s movement, particularly if it’s a singing male or is exhibiting other territorial behavior.   Do we see any behavior indicating where the nest might be found?  Concurrently, you want to look and listen to determine whether you have any other individuals of that species, and if so, map them too.

Here's one of 3 maps that I filled in during a single visit of my area search plot

At the end of the survey, we’ll end up with a map of all of our bird locations, criss-crossed with lines – solid ones indicating the movements of a particular individual, dashed lines indicate that we had different individuals, along with a few scribbled behavioral notes.  The day’s not done yet, though!  We’ll transfer each species’ locations, lines and notes to a species-specific map, that will eventually encompass all of the data for that species from all of the visits.  Before each visit, we’ll scrutinize those maps, and figure out where the territory boundaries are unclear and where we need to spend some more time.  Then, at the end of our 8 to 10 visits, we’ll draw our territory boundaries, and summarize our findings.

If you squint, you can make out letters marking locations: the first visit is A, the 2nd visit, B, and so on.

The area searches are useful for a lot of purposes – they give us detailed natural history information, and because they provide such detailed location information, they’re excellent at monitoring changes in habitat and bird communities through time, so they’re incredibly useful to monitor habitat restoration projects.  Plus we’re able to use them to do some calibrating of our extensive program of point count surveys – by conducting point counts on the area search plots, we’re able to compare what our point count surveyors record to the mapped territories, which helps us determine detection rates.

You don’t need UTM grids and GPS units to do your own territory mapping, though.  Find your favorite park on (for example) google maps, switch to satellite view, zoom in, and print it out.  With a pencil and your binoculars, you’re now set to map out territories of the bird community – or just a species or two of interest.  When you’ve mapped out a territory, take a look at it  - what does it tell you about that species’ habitat/structural needs?  Where is the nest located relative to the territory boundary?  If a pair renests, with either a replacement clutch or a second brood, do their territory boundaries shift?   As they move along in breeding stages, how do their movements change?   Do their defended areas contract, or expand?  And of course, spot mapping doesn’t have to be limited to the breeding season, you can also see how birds’ uses of various habitats changes across the seasons.  All fun things you can explore with mapping! 

Happy birding,

- Jen

Clark County Species List, 2013

Summer Tanager at Warm Springs

Ha! Look what I found!  Tucked into a 3 foot tall stack of data was the list of species my NBC crew recorded in Clark County this year, mid-April to mid-June.  It had hung on our field house's refrigerator and was carefully tended whenever folks returned.  Looking through it again, it brought back more than a few fun memories, and I thought some folks might be interested.  It’s certainly not an exhaustive list of what can be found down there  – we weren’t hitting hot spots in order to build a list, we were visiting random locations within the County, which sometimes took us to really birdy places, and other times took us to some barren creosote scrub with a couple of Black-throated Sparrows.  It was a lot of fun, but – as my crew can attest – there’s a lot of really tough terrain down there!  Anyway, here it is …

1. Canada Goose
2. American Wigeon
3. Mallard
4. Northern Shoveler
5. Chukar
6. Ring-necked Pheasant
7. Gambel’s Quail
8. Pied-billed Grebe
9. Eared Grebe
10. Western Grebe
11. Clark’s Grebe
12. Double-crested Cormorant
13. Least Bittern
14. Great Blue Heron
15. Great Egret
16. Snowy Egret
17. Black-crowned Night-Heron
18. White-faced Ibis
19. Turkey Vulture
20. Osprey
21. Northern Harrier
22. Sharp-shinned Hawk
23. Cooper's Hawk
24. Common Black-Hawk
25. Swainson's Hawk
26. Zone-tailed Hawk
27. Red-tailed Hawk
28. Virginia Rail
29. Sora
30. American Coot
31. Snowy Plover
32. Killdeer
33. Black-necked Stilt
34. American Avocet
35. Spotted Sandpiper
36. Ring-billed Gull
37. Rock Pigeon
38. Eurasian Collared-Dove
39. White-winged Dove
40. Mourning Dove
41. Greater Roadrunner
42. Barn Owl
43. Western Screech-Owl
44. Great Horned Owl
45. Burrowing Owl
46. Lesser Nighthawk
47. Common Poorwill
48. Vaux's Swift
49. White-throated Swift
50. Black-chinned Hummingbird
51. Anna's Hummingbird
52. Costa's Hummingbird
53. Broad-tailed Hummingbird
54. Belted Kingfisher
55. Ladder-backed Woodpecker
56. Hairy Woodpecker
57. Northern Flicker
58. Gilded Flicker
59. American Kestrel
60. Peregrine Falcon
61. Prairie Falcon
62. Olive-sided Flycatcher
63. Western Wood-Pewee
64. Willow Flycatcher
65. Gray Flycatcher
66. Dusky Flycatcher
67. Black Phoebe
68. Say's Phoebe
69. Vermilion Flycatcher
70. Ash-throated Flycatcher
71. Brown-crested Flycatcher
72. Western Kingbird
73. Loggerhead Shrike
74. Bell's Vireo
75. Gray Vireo
76. Plumbeous Vireo
77. Cassin's Vireo
78. Warbling Vireo
79. Western Scrub-Jay
80. Pinyon Jay
81. Clark's Nutcracker
82. Common Raven
83. Horned Lark
84. Tree Swallow
85. Violet-green Swallow
86. Northern Rough-winged Swallow
87. Barn Swallow
88. Mountain Chickadee
89. Juniper Titmouse
90. Verdin
91. Bushtit
92. Red-breasted Nuthatch
93. White-breasted Nuthatch
94. Pygmy Nuthatch
95. Rock Wren
96. Canyon Wren
97. House Wren
98. Marsh Wren
99. Bewick's Wren
100. Cactus Wren
101. Ruby-crowned Kinglet
102. Blue-gray Gnatcatcher
103. Black-tailed Gnatcatcher
104. Western Bluebird
105. Mountain Bluebird
106. Townsend's Solitaire
107. Swainson's Thrush
108. Hermit Thrush
109. American Robin
110. Northern Mockingbird
111. Bendire's Thrasher
112. Crissal Thrasher
113. Le Conte's Thrasher
114. European Starling
115. Phainopepla
116. Orange-crowned Warbler
117. Lucy's Warbler
118. Virginia's Warbler
119. MacGillivray's Warbler
120. Common Yellowthroat
121. Yellow Warbler
122. Yellow-rumped Warbler
123. Grace's Warbler
124. Black-throated Gray Warbler
125. Townsend's Warbler
126. Wilson's Warbler
127. Yellow-breasted Chat
128. Green-tailed Towhee
129. Spotted Towhee
130. Abert's Towhee
131. Chipping Sparrow
132. Brewer's Sparrow
133. Black-chinned Sparrow
134. Vesper Sparrow
135. Lark Sparrow
136. Black-throated Sparrow
137. Song Sparrow
138. Lincoln's Sparrow
139. White-crowned Sparrow
140. Dark-eyed Junco
141. Summer Tanager
142. Western Tanager
143. Black-headed Grosbeak
144. Blue Grosbeak
145. Lazuli Bunting
146. Bobolink
147. Red-winged Blackbird
148. Western Meadowlark
149. Yellow-headed Blackbird
150. Great-tailed Grackle
151. Brown-headed Cowbird
152. Hooded Oriole
153. Bullock's Oriole
154. Scott's Oriole
155. Cassin's Finch
156. House Finch
157. Pine Siskin
158. Lesser Goldfinch
159. American Goldfinch
160. House Sparrow

Happy birding!

Jen

Farewell to the Sage Sparrow; Hello to the Bell's Sparrow and Sagebrush Sparrow within Nevada

In 2010, the Sage Sparrow was classified as a species of conservation concern within Nevada.  In the latest changes to the AOU (American Ornithologists’ Union) Checklist, the Sage Sparrow has been split into two species, the Bell’s Sparrow and the Sagebrush Sparrow.  Both of these species breed within Nevada.  The Sagebrush Sparrow (Artemisiospiza nevadensis) is far more common within the state, and found through much of the Great Basin, predominantly within sagebrush, but also within greasewood community types.  A typical example of the Sagebrush Sparrow’s breeding habitat can be seen in the header photo at the top of this page – I heard several territorial males singing within this stand of sagebrush, and one individual was carrying food.

The desert race of the Bell’s Sparrow (Artemisiospiza belli ssp. canescens) is also found breeding in southern and western Nevada, where we have found it primarily within relatively dense stands of Atriplex (saltbush), though it can also be found in sagebrush within its range.  Note that most maps I’ve seen showing the breeding range of the (canescens) Bell’s Sparrow do not include its range within southern Nevada.  However, we have confirmed them breeding within salt desert both east and west of the Spring Mountains.  Their range continues northward along the western edge of the state, towards Bishop.  Below is an example of Bell’s Sparrow breeding habitat near the Spring Range in Clark County – within 50m of this location, I watched an adult Bell’s Sparrow feeding a fledgling.

In 2007, Carla Cicero and Ned Johnson documented a zone of contact between the 2 species in the Owens Valley, near Bishop [1].  Walter Szeliga provided a useful discussion on Nathan Pieplow's earbirding.com of the differentiation between the former subspecies of the Sage Sparrow, including a map from Cicero (2010) showing the known range of the Bell’s Sparrow (ssp. belli), Bell’s Sparrow (ssp. canescens), and Sagebrush Sparrow.  The map is useful for Nevadans in approximating the extent of the Sagebrush Sparrow, but does miss the Bell’s Sparrows breeding in the southern portions of the state.  In the end, Szeliga concludes that the canescens subspecies’ song appears confusingly intermediate between the belli song and the Sagebrush Sparrow’s song, but speculates that some of this confusion may be due to clinal differences in song, or perhaps incorrectly identified examples.  Personally, I haven’t surveyed the canescens subspecies of the Bell’s Sparrow where it nears its contact zone in Bishop, but the breeding individuals I have heard singing in Clark County have sounded quite different than Sagebrush Sparrows, with a song that seems shorter, flatter, and less musical.

During winter and migration, we have both species in southern Nevada, and absent song or a good look, differentiating between them is a tad difficult.

Happy birding-- and stay tuned!

Jen

[1] Cicero, Carla, and Ned K Johnson.  2007.  Narrow contact of Desert Sage Sparrows (Amphispiza Belli Nevadensis and A.B. Canescens) in Owens Valley, Eastern California: Evidence from Mitochondrial DNA, Morphology, and GIS-Based Niche Models.  Ornithological Monographs 63: 78-95.

The Nevada Bird Count 2013 Has Wound Down, Part the Last

And with this installment, I grudgingly admit that the NBC is over for yet another year.  As you probably remember from previous posts, awhile back I asked the crew to shoot me an anecdote from their season, and here’s a final few –

Dennis:  [Becca and I had a] sighting of a Big Horn Sheep at the McCarran Ranch on the morning of our first area search in May. Becca dropped me off at my plot before going across the river to her’s …. I was at the car putting on my boots and gaiters when she came running back yelling “Big Horn Sheep! Big Horn Sheep!” I ran down the dirt road with her past the amphitheater only to see the sheep running away from us east down the road. After Becca left I started down the road again on the way to my plot when I saw the sheep approaching me again. I slowly took off my backpack and got out my camera, but just as I got the camera up to shoot it turned and ran away. I did however get a shot of it running away. I told Chris Sega [The Nature Conservancy] about it and he was quite excited. Apparently Nevada Department of Wildlife released some in the hills to the south of McCarran Ranch and they have been coming down to the river to drink and feed, but this was the first time one had been seen on the north side of the river.

 

Becca:  This was a great year for critters. I was area searching around the McCarrran Ranch east end pond when I came face to face with a skunk. He stopped. I stopped. He stared at me. I stared back. He raised his tail, and I turned my tail around in a hurry. Who was I to interrupt a skunk’s morning stroll?

Laura:  It feels like such a privilege to see what we see and work where we work. Private lands and reservations aside, it's not too terribly difficult to access some of the sites that we do provided you have four wheel drive and the gumption to do so. But most people stay on the beaten path which I suppose is best for us. The wildlife and soaring vistas I've seen on the job, the latter usually earned after an arduous hike, are sights the average person probably never sees. I'm glad to have witnessed them and in some small way aid in making sure they'll remain in good condition for years to come. My two favorite sightings hands down: a roadside Gila Monster and a female Greater Sage-Grouse my partner and I flushed in the Desatoyas.

I just had an interesting realization the other day, as I was writing about my Warm Springs Natural Area territory maps and going through nest photos – I had a snag where I observed 3 different pairs building nests – Brown-crested Flycatcher, Western Kingbird, and Lucy’s Warbler.  And every single one ended up abandoning their nest either late in construction or shortly after nest completion - it's a little hard to tell with cavity-nesters!  This seemed unlikely to have just happened.  I was trying to think about what was special/different about this snag.  It was probably the major perch used by Brown-headed Cowbirds on the plot, but while they could conceivably get past one of the Western Kingbirds (though they’re pretty rare hosts), it’s difficult to see them getting into the Flycatcher’s cavity (I suspect it’s possible, but unlikely, and there are no North American records of them as hosts mentioned in their BNA account), and fitting into that Lucy’s Warbler fissure/cavity was even more unlikely – it was a pretty small opening.  The only other thing I could think of was (well, other than random chance) maybe an ant colony had moved in and swarmed.  I don't remember seeing high levels of ant activity at the snag, but I wasn't really looking, and they're certainly in the area.  Any other ideas?

Western Kingbird nest, mid-construction - bit of an odd location for a Kingbird!

  

Lucy's Warbler nest cavity

Well, that’s it for the anecdotes for this season.  Thanks again to my awesome field crew:  Becca, Brian, Dave, Dennis, Kathryn, Kelly, Laura, Rayann, Russ, Rya, Sam, and Sue.  Seriously, you guys rock beyond the telling of it!

 

Happy birding,

-- Jen

Pine Forest Range Species List, July 9-10

I had a couple of folks email me about the full species list for our NBC crew’s two-and-a-bit days in the Pine Forest Range, so here it is.  One of the things we were trying to concentrate on was breeding evidence, so I’ve included breeding status, when we had either probable or confirmed breeding.  We found 70 species during our surveys; 29 of these were confirmed breeders, and a further 5 were probable breeders.  Six of them were of conservation concern (there's an asterisk in the number column).

A fun time in the mountains!

Num.	Species	Breeding Status
1	Gadwall	Probable
2	Mallard	Confirmed
3	California Quail	Confirmed
4	Horned Grebe
5	Turkey Vulture
6	Northern Harrier
7	Cooper's Hawk
8	Red-tailed Hawk	Confirmed
*         9	Golden Eagle
10	American Kestrel
11	American Coot
12	Killdeer	Probable
13	Spotted Sandpiper
14	Long-tailed Jaeger
15	Mourning Dove
16	Great Horned Owl
17	Common Nighthawk
18	Common Poorwill
*       19	Calliope Hummingbird
20	Red-naped Sapsucker	Confirmed
21	Northern Flicker	Confirmed
22	Hammond's Flycatcher	Probable
23	Dusky Flycatcher	Confirmed
24	Cordilleran Flycatcher
25	Say's Phoebe
26	Warbling Vireo	Confirmed
27	Clark's Nutcracker	Confirmed
28	Common Raven
29	Tree Swallow	Confirmed
30	Violet-green Swallow	Confirmed
31	Cliff Swallow
32	Mountain Chickadee
33	Bushtit
34	Red-breasted Nuthatch
35	White-breasted Nuthatch
36	Rock Wren	Confirmed
37	Bewick's Wren
38	House Wren	Confirmed
39	Ruby-crowned Kinglet
40	Mountain Bluebird	Confirmed
41	Townsend's Solitaire
42	Swainson's Thrush	Probable
43	Hermit Thrush	Confirmed
44	American Robin	Confirmed
*       45	Sage Thrasher
46	Orange-crowned Warbler	Confirmed
*       47	Virginia's Warbler
48	MacGillivray's Warbler
49	Yellow Warbler	Confirmed
50	Yellow-rumped Warbler	Confirmed
*       51	Green-tailed Towhee	Confirmed
52	Spotted Towhee	Confirmed
53	Chipping Sparrow	Confirmed
*       54	Brewer's Sparrow	Confirmed
55	Vesper Sparrow	Confirmed
56	Lark Sparrow
57	Fox Sparrow	Confirmed
58	Song Sparrow
59	Lincoln's Sparrow
60	White-crowned Sparrow	Confirmed
61	Dark-eyed Junco	Confirmed
62	Western Tanager	Probable
63	Black-headed Grosbeak
64	Lazuli Bunting
65	Western Meadowlark	Confirmed
66	Brewer's Blackbird	Confirmed
67	Brown-headed Cowbird
68	Cassin's Finch	Confirmed
69	House Finch
70	Pine Siskin