Bird adventures on Anaho Island

Cormorant nests

In January, we began our bird surveys on Anaho Island, to help document use of the island by birds other than colonial waterbirds.  Closed to the public, Anaho Island is both a National Wildlife Refuge managed by the US Fish and Wildlife Service, and a part of the Pyramid Lake Paiute Reservation, patrolled by the Tribe’s Pyramid Lake Rangers.  It was established to protect breeding colonies of waterbirds, particularly American White Pelicans – the pelican colony there is one of the two biggest in the western United States.  For now, our surveys extend across the entire island – as the breeding colonies of pelicans, cormorants, gulls and so on, re-establish themselves in spring, our survey area will shrink to only those areas where we cannot disturb them.

We completed our first winter survey in January – though given the blue skies, warm weather, and green grass, it didn’t feel too much like winter!  We didn’t see anything unexpected on this visit, but I certainly was impressed by the sheer numbers of Rock and Canyon Wrens.  We’re definitely looking forward to documenting the changes in the bird community here across the seasons - we’ll keep you posted!

Happy birding,
Jen

From the Great Salt Lake to Las Vegas Wash: Pelicans

On October 31, at Las Vegas Wash, I spotted a small group of pelicans - two of which had been banded.  One of the bird's tags were readable - two numbers and a letter in white writing on a green tag.  It turns out it had been banded as a chick on July 23rd up in the Great Salt Lake.  Here's a short article that the Review-Journal published earlier this year on the banding there.  Keep your eyes peeled!  And remember, if you find banded birds (pelicans or otherwise), please do report their bands to the Bird Banding Lab here - though with the larger wing tags like those on these pelicans (since you're not likely to be seeing the leg bands), you'll have to use their email address.

Happy birding!
Jen

Fall/Winter 2014 Projects

View from Las Vegas Wash

It’s been a busy fall here at GBBO!  Much of what we’ve been doing is working through the piles of data accumulated during the breeding season – but we’ve managed to make it out into the field, as well.  Among our projects were:

Anaho Island – in January, we will begin a year-long project looking at non-colonial waterbird use of Anaho Island.  This October, we visited the island to scope out survey locations, and see where the American White Pelican colony was located.  Stay tuned!

Crescent Dunes, Tonopah - in September, we began a pilot monitoring season at the Crescent Dunes Solar Power Plant near Tonopah.  This plant is due to begin generating power in early 2015; we’ll be involved in biological monitoring here for the next few years to document bird use and potential mortalities.  This will help to ensure that any impacts are well-documented, and will contribute to the development of mitigation strategies to minimize impacts on birds.

Las Vegas Wash – in September, we started up year-round bird surveys:  every two weeks, one of our surveyors conducts point counts on the Wash.  In October, we attacked the vegetation survey portion of the project – many thanks to Kelly and Dave for their hard work and great attitude – there’s nothing quite like having to run out a measuring tape through 70 meters of solid quailbush!

Lower Colorado River Project – the LCR crew had a successful bird survey season this spring/summer, and followed it up with vegetation surveys throughout September and October.  Here’s a post from a previous year’s veg surveys along the LCR, showing what it’s like.  Intrepid souls, who always seem to find the fun – even in tamarisk!

Nevada Bird Count – while the bird surveys finished in early July, and our main crew left in late July, Kelly and Dave remained on the vegetation survey circuit into November, finishing up habitat surveys in blackbrush habitats within the Mojave Desert, and pinyon-juniper habitats within the Pine Nut Range, near Carson City.  Thanks, guys!

Warm Springs Natural Area – in September, we conducted our fall bird surveys, and in October/November, the final vegetation surveys were finished up.  Dave informs me that however impressed he was by his 70 meters of quailbush, he was even more impressed by his 50 solid meters of mesquite thicket.  He’s finishing up the data entry now – next month the habitat modelling begins!

Waterbirds –  we continued to monitor fish-eating waterbird numbers at Walker Lake and several other terminal lakes in western Nevada, including Pyramid Lake.  Due to continued declines in the water level and Walker Lake, and corresponding increases in dissolved solids in the lake water, fish populations have crashed and the avifauna of the lake reflects these changes, with fish-eating birds numbers reaching very low levels, and numbers of invertebrate feeders (notably the small grebes) reaching very high levels during parts of the year.  Continued bird monitoring will help to document improvements in the lake's ecology if current efforts to acquire more inflow are ultimately successful.  

As you can see, we’ve been keeping busy – and now prepping for the 2015 field season begins!  Have a wonderful holiday, and all the best for the New Year!

Jen

Breeding White-faced Ibis in Nevada

[Note: this spiel was written quite some time back, but I thought you might find it interesting all the same! -- Jen]

In 2009 through 2011, Great Basin Bird Observatory teamed with Nevada Department of Wildlife (NDOW) to survey colonial waterbirds throughout the state, including White-faced Ibis, as a part of a regional evaluation led by the U.S. Fish and Wildlife Service and American Bird Conservancy.  White-faced Ibis, dark-colored wading birds, have a long downwardly-curved bill with which they probe through the mud and debris of wetlands and agricultural fields in search of their prey – in the Great Basin, they feed mostly on earthworms and insect larvae.  

In the 1960s and 1970s, pesticides and habitat loss caused the ibis population to crash, across their range[i].  However, in the 1980s and 1990s, they began increasing again; now, the Intermountain West population is considered to be of only moderate conservation priority[ii].  While the regional trend is stable or increasing, there is concern that Nevada’s population may again be declining[iii].  Evaluating White-faced Ibis populations on a state-wide level can be difficult, however, since they are nomadic, with colonies moving as water levels fluctuate.  

The Lahontan Valley, particularly Carson Lake, has traditionally been one of the most important White-faced Ibis breeding areas within the Great Basin, and in high water years supports the bulk of Nevada’s breeding population.  Breeding numbers vary dramatically here, from 0 (e.g., 1974) to 9000 pairs (e.g., 1997)[iv].  Our results supported this pattern: in 2009, a low water year, NDOW recorded 100 breeding ibis; with the higher waters seen in 2011, 6940 breeding ibis were recorded.  The Humboldt River, Ruby Valley, and Quinn River also supported large numbers of breeding ibis, and formed the bulk of Nevada’s population during low water years in the Lahontan Valley.

While pesticide impacts have lessened in past years for the majority of the Intermountain West’s population, eggshell thinning as a result of DDT (and DDE, its metabolic byproduct) remains an important problem for Carson Lake’s ibis, particularly for those breeding early in the season.  While DDT was banned from use within the United States in 1972, DDE levels in Carson Lake ibis eggs have remained high over time[v].  Michael Yates and others[vi] reported that many of Carson Lake’s ibis winter in the Mexicali and Imperial Valleys of Mexico and California, and that these birds had high levels of DDE.  Unfortunately, White-faced Ibis appear to be physiologically susceptible to DDE/DDT, and their life history increases their chance of exposure: they tend to feed in agricultural fields that may have been subjected to past pesticide applications, and their favored prey are earthworms, which tend to bioaccumulate DDE from soils.  In addition, they tend to breed shortly after arriving on their breeding grounds, while their systems still contain DDE, which may explain why earlier nesting individuals tend to have greater eggshell thinning – individuals nesting later have been able to feed on uncontaminated prey, and their DDE levels and eggshell thinning are consequently reduced.

While our joint colonial waterbird project is over, NDOW continues to regularly survey the major White-faced Ibis colonies, including those in the Lahontan Valley, and we continue to maintain our statewide colonial waterbird database.  If you have information on breeding ibis colonies (or other colonial waterbirds), locations and/or numbers, we’d love to hear from you!  Many thanks to our partners at Nevada Department of Wildlife for sharing their survey results for this project, especially Brad Bauman, Pete Bradley, Jenni Jeffers, and Larry Neel.

---

[i] Ryder, Ronald A. and David E. Manry. 1994. White-faced Ibis (Plegadis chihi), No. 130.  The Birds of North America (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology.

[ii] Ivey, Gary, and Caroline P. Herziger.  2006.  Intermountain West Waterbird Conservation Plan.  Version 1.2.  February 2006.  A plan associated with the Waterbird Conservation for the Americas Initiative.  Published by U.S. Fish and Wildlife Service Pacific Region, Portland, Oregon.

[iii] Great Basin Bird Observatory.  2010.  Nevada Comprehensive Bird Conservation Plan, Version 1.0.  Great Basin Bird Observatory, Reno, NV.  Available online at www.gbbo.org/bird_conservation_plan.html

[iv] Ivey and Herziger 2006; Oring, Lewis W, Larry Neel, and Kay E Oring.  2001.  Intermountain West Shorebird Plan.  Version 1.0. 

[v] Henny, Charles J. 1997.  DDE still high in White-faced Ibis eggs from Carson Lake, Nevada.  Colonial Waterbirds 20(3): 478-484.

[vi] Michael A. Yates, Mark R. Fuller, Charles J. Henny, William S. Seegar, Jaqueline Garcia. 2010.  Wintering area DDE source to migratory white-faced ibis revealed by satellite telemetry and prey sampling. Ecotoxicology 19:1, 153-162.

Citizen Science projects

I recently came across Birdwatching magazine’s rundown of citizen science projects, and thought I’d share.  There look to be some really interesting ones: enjoy!

http://www.birdwatchingdaily.com/featured-stories/year-round-citizen-science-projects/

Happy birding,

Jen

Migration

It’s that time of year again!  Kelly, Dave and I arrived at Warm Springs Natural Area to do some migration surveys – along with some habitat surveys.  It’s been a great week and a half of birding, and a good opportunity to get up close and personal with mesquites and quailbush.  Plus: adventure!  We were down there during an impressive cloudburst – one gauge in Moapa evidently reported more than 3 and a half inches of rain in 90 minutes.  Fortunately we weren’t in the field at the time, and were able to view the flooding from the top of a tall hill!  Deeply impressive rainfall … followed by impressively deep gloopy mud.

Where's Dave?

Oh, there he is: tunneling through the quailbush!

The most common of our migrants were Warbling Vireos (by a lot!), Orange-crowned Warblers, Western Tanagers, and Wilson’s Warblers.  My most memorable sightings were the Black-tailed Gnatcatcher female feeding her two very noisy fledglings low down in a honey mesquite; the Baltimore Oriole male flitting from cottonwood to palm; and the shock of having a flock of Pinyon Jays calling overhead, flying north.  Here’s the overall species list so far – more surveys to come! 

Gambel's Quail

Great Blue Heron

Turkey Vulture

Cooper's Hawk

Red-tailed Hawk

American Kestrel

Virginia Rail

Eurasian Collared-Dove

Mourning Dove

Greater Roadrunner

Belted Kingfisher

Ladder-backed Woodpecker

Ants re-building tunnels, post-flood

Western Wood-Pewee

Gray Flycatcher

Black Phoebe

Say's Phoebe

Vermilion Flycatcher

Western Kingbird

Loggerhead Shrike

Bell's Vireo

Warbling Vireo

Western Scrub-Jay

Pinyon Jay

Common Raven

Barn Swallow

Verdin

Bewick's Wren

House Wren

Marsh Wren

Ruby-crowned Kinglet

Blue-gray Gnatcatcher

Black-tailed Gnatcatcher

Northern Mockingbird

Crissal Thrasher

Phainopepla

Orange-crowned Warbler

Lucy's Warbler

Nashville Warbler

MacGillivray's Warbler

Common Yellowthroat

Yellow Warbler

Yellow-rumped Warbler

Black-throated Gray Warbler

Wilson's Warbler

Yellow-breasted Chat

Green-tailed Towhee

Abert's Towhee

Chipping Sparrow

Brewer's Sparrow

Vesper Sparrow

Song Sparrow

White-crowned Sparrow

Summer Tanager

Western Tanager

Black-headed Grosbeak

Red-winged Blackbird

Yellow-headed Blackbird

Brown-headed Cowbird

Bullock's Oriole

Baltimore Oriole

House Finch

Lesser Goldfinch

American Goldfinch

Western Scrub-Jay Genetics

Western Scrub-Jay that wintered in Moapa

There has been a fair amount of talk over recent years about splitting the Western Scrub-Jay.  Earlier this year, a fascinating article, written by Fiona Gowen and others, was published about Western Scrub-Jay genetics across their range – long story short, they found 5 genetic clusters, Pacific coastal, interior U.S., Edwards Plateau (Texas), northern Mexico, and southern Mexico.  They’re recommending further sampling of the Edwards Plateau and northern Mexico jays to determine what’s really going on with them, but in the meantime, they’re recommending that the Western Scrub-Jay be split into 3 species (the Edwards Plateau and northern Mexico birds would be lumped with the interior U.S. species, unless and until more information comes to light).

This study is of particular interest to Nevada birders, since the Reno-Carson City area is the primary zone of contact between the Pacific Slope and Interior U.S. populations.  Plus some very helpful figures and tables are included.  Hope you enjoy it, too!

Happy birding,

Jen

(A quick note on the photos - there were a fair number of Western Scrub-Jays that wintered in Moapa this year; this individual was one of the last to leave this spring (photo taken 2 May).  Note the differences in color/brightness and in beak size/shape, compared to the Reno-Sparks birds.)

Western Scrub-Jay from Reno-Sparks

Western Scrub-Jay from Reno-Sparks