UPDATE: Kirtland’s Warbler 2008 Breeding Success in Wisconsin and Michigan

© photo from U.S. Fish and Wildlife Service

As many of you may already know (and per my earlier posting below from June 27 and July 8, 2008), the Kirtland’s Warbler (Dendroica kirtlandii) is one of North America’s rarest neotropical migrant songbirds.

As brief background, the species was not discovered to breed in Michigan until 1903 when Norman A. Wood discovered the first nest in Oscoda County in northern lower Michigan. Until 1996, all nests were found within 60 miles of this site. Since then, a small number of nests have been found each year in Michigan's Upper Peninsula. Until last year, only periodic nesting occurred in Wisconsin and the province of Ontario.

But 2007 and 2008 changed everything. Successive discoveries during the last two breeding seasons of Kirtland’s in similar locations (and a new Wisconsin County added in 2008) have changed the boxscore appearance. It’s arguably now safe to suggest that Kirtland’s nests annually in both Michigan and Wisconsin.

What follows provides an update and summary of the species’ 2008 breeding success in Wisconsin. The chart, below, provides an update of totals for Michigan, Wisconsin and Ontario in 2007 and 2008.

Wisconsin’s documented Kirtland’s total in 2008 is 10 (with 9 out of the 10 banded and fitted with colored bands to, hopefully, monitor their presence in future breeding seasons if and when they return to North America next spring). Five nests were observed in Adams County (central WI) while two different singing males were heard in Marinette County (northern WI).

In all, volunteers and professional biologists monitored 12 Wisconsin counties for Kirtland’s in 2008. Beyond Adams and Marinette Counties, survey teams reported hearing or seeing Kirtland’s at several sites in Vilas and Jackson Counties. Ensuing confirmation by US Fish and Wildlife and WI DNR biologists of these reports was not possible.

(# = In addition, another Kirtland’s male was reported from a far northern WI county – Bayfield – and the female associating with the male was also seen. However, no additional sightings were repeated and a nest was never found, so it remains uncertain as to whether breeding occurred at this site.)

Meanwhile, reports from the US Fish and Wildlife Service’s monitoring biologists in Michigan suggest fair success among this season’s resident breeding population in six north-northcentral counties that totaled 1,791 singing males –- an increase of 94 in comparison to the 1,697 singing males reported in 2007.

The combined total of singing males heard throughout Michigan, Wisconsin, and Ontario in the 2008 breeding season was 1,801 males (see below "chart" that breaks down the breeding numbers for these areas.)

(Interestingly, as a digression of thought while you read this account, note that all of the Kirtland’s have currently dispersed and/or migrated south en route to their Bahama Island non-breeding grounds. Undoubtedly, some of the early migrants that left Wisconsin and Michigan by the first week of July may have already arrived on their non-breeding territory within the Bahamas.

Whether other individuals, in addition to other migrating bird species, survived such calamities as Gustav, obviously remains unclear. It’s safe to suggest, however, that mortality is a dominant result of songbird migration, with estimates ranging from 30 to 50 percent mortality.)

*

Kirtland’s Warbler 2007 Breeding 2008 Breeding

Wisconsin 8 males
(3 nest sites in one county) 10 (two counties)
(# above remark = three?)
Michigan 1,697 males 1,791 males
Ontario 2 males 1 male

References
(and thanks for their help) that I used to create this post:

Tom Schultz, Dr. Noel Cutright, and The Northeast Wisconsin Birder, Volume 7, Issue 5, June-July, 2008

Vagrant Eastern Wood-Warblers in the West….

……and it’s the best time to see them.

September and October are often the best months to see eastern wood-warblers in coastal areas (such as northern California, including Point Reyes National Seashore in Marin County).

But you can also see them inland, especially within dense, tangled growth along rivers and creeks.

Which eastern wood-warbler species appears in this photo?

It was photographed by Martin Meyers in the Sacramento area on 10/1/04. (The answer appears at the bottom of this entry.)

According to one study published as “On the Occurrence of Eastern Wood Warblers in Western North America” (George Austin, Winter, 1971) in The Condor, 28 species of eastern wood-warblers have been detected in California. This study does not account for more recent published data.

Among the 28 species, the rarest to see is Cerulean, Prothonotary, Worm-eating, Golden-winged, Blue-winged, Prairie, Louisiana Waterthrush, and Mourning.

Other wood-warbler species that are often considered rare or vagrants in California have wintered in recent years, such as Black-and-White, Palm, Northern Waterthrush, and American Redstart*. At least five other species are believed to have wintered one or more times: Tennessee, Northern Parula, Chestnut-sided, Blackpoll, and Ovenbird.

As for where you can see vagrant eastern wood-warblers on the West Coast, I do not intend this entry to be a comprehensive tell-all summary. Instead, I’m featuring a well known “vagrant trap” -- Point Reyes National Seashore (PRNS) –- as one suggested destination that you may choose for your sleuthing effort. Within PRNS, checkout the Monterey Cypress groves that occur as “islands of green refuges” at the Outer Point amidst the dairy farms and chaparral. These groves represent wayside oases with dense vegetation providing food resources amidst otherwise inhospitable conditions — for eastern wood-warblers that, in most cases, have lost their way as they dispersed or migrated from breeding grounds.

Disoriented, these eastern wood-warbler individuals are often at the extreme western point of their post-breeding season movement. Many may even continue flying farther west, winging their way over the ocean with oblivion their unintended destination.

The lucky ones find regugia within eventual landfall, such as a group of seven islands called the Farallone Islands (27 miles west of San Francisco and 20 miles south of Point Reyes National Seashore's Outer Point). It’s another ideal venue where researchers observe eastern wood-warblers – with the tenancity of these lost survivors surely admirable. But, alas, the cruel penalty for their aimless perigrination often means an unfortunate early exit from our world – and the Outer Point and Farallones serve as “purgatory” waysides before fate interludes.

(* = Note an annual population of American Redstart nests in northwestern CA, I do not consider sightings of it on the West Coast to be absolute vagrant/accidental observations. Instead, it’s safer to consider sightings of this species in late summer/autumn are either West Coast or East Coast breeding individuals.)

(Chestnut-sided Warbler appears in the above photo that you can enlarge by clicking on it.)

Wood-Warbler Resources R Us: See Below......

......as there's plenty of amazing, helpful wood-warbler web sites and other related birding resources for you to peruse.

(The identity of the wood-warbler species in the above photo is revealed in a caption below/right column that repeats the same photo of this individual.)

Here's a partial list to which I'll add in the near future (below). For now, check out the following:

{Note: It's flattering to see the Cornell Lab of Ornithology also likes the monicker "Warbler Watch :-) (below web site link).}

*

http://www.giffbeaton.com/warblers.htm

http://dendroica.blogspot.com/2008/07/evolution-of-wood-warblers.html

http://www.birdnote.org/search-results.cfm

http://www.ohloneaudubon.org/birdingresource.htm

http://minnesotabirdnerd.blogspot.com/

http://www.birdsource.org/index.html
(Cornell Laboratory of Ornithology’s “Warbler Watch” program)

http://10000birds.com/wood-warblers-on-the-move-and-a-little-quiz.htm
(10,000 Birds)

Non-Migrating Wood-Warblers?

Yes.......

....and it’s easy to overlook the fact that the majority of approximately 116 wood-warbler species
(Parulidae family) do not migrate and live year-round in the tropics.

Approximately 64 species of wood-warblers never occur farther north than Mexico.

The true migrators (i.e., neotroprical migrants) – 52* wood-warbler species, such as the Blackburnian, Cerulean, Prothonotary, to name merely three -- with which we enjoy steeping our senses after (too) long winters are primarily breeding residents only within some of the lower 48 USA states.

Interestingly, some states (e.g., CA, TX, GA, FL, and a few southeastern USA states) host one or more wood-warbler species as either winter and/or permanent residents (e.g., The above photo features Common Yellowthroat, thanks to Martin Myers © whose image of this Nevada individual in April is one of 15 subspecies within the Common Yellowthroat species found throughout North America where it breeds in all of the lower 48 USA states.)

Even mid-Atlantic, New England and upper Midwest states regularly host small populations of wood-warbler species that remain year-round. Hardy species surviving northern latitude winters may typically include Yellow-rumped Warbler and Common Yellowthoat, and, less commonly, Yellow-breasted Chat and Palm Warbler. All four of these species are uncommonly to sometimes observed during annual Christmas Bird Counts (CBC) that occur in mid- to northern-latitude states. Whether CBC detections are simply truant individuals that eventually flee winters grip and move south remains uncertain from one year to the next.
But, if suitable micro-habitat conditions occur and the winter season is not too severe, then all four of the aforementioned species may remain during some years.

In general, and in sum, the greater northern latitudes host few numbers of and fewer non-breeding season wood-warblers than southern latitudes corresponding to, say, S. Carolina, Georgia, Florida and other southeastern states.

What about the other 64 remaining tropical resident species (that live primarily outside the USA)? -- the majority of which are wood-warbler species that do NOT migrate. These species’ life histories within the tropics feature some distinct differences from their migrating first-cousins (e.g., Blackpoll and other typical northern North America wood-warbler species), including:

1) tropical resident wood-warbler species tend to have sexes that exhibit the same plumages (unlike the Blackpoll where the female looks starkly different than the male); and 2) the most brilliant of the tropical wood-warbler species express the same bright colors throughout the year; 3) the nesting period for tropical wood-warbler species is often longer.

(* = Note that only 52 of the 116 wood-warblers (Parulidae family) are
typically reliably seen in the lower 48 USA states each year, according to "A Field Guide to Warblers of N. America" authors Jon L. Dunn & Kimball L. Garrett.)

New Kirtland’s Warbler Sighting in Wisconsin

. . . Federally endangered species reported in third WI county (Bayfield County) this breeding season (2008)

. . . To find the following article online as of 7/8/08, go to:
http://www.madison.com/wsj/home/local/index.php?ntid=295036

Dateline:
Nicolet National Forest
by PEDRO OLIVEIRA JR.
Wisconsin State Journal Reporter
608-252-6120
poliveira@madison.com

A pair of Kirtland's warblers, one of the rarest North American birds, has been spotted for the first time in northern Wisconsin, the U.S. Fish and Wildlife Service confirmed last week.

"It's been a little more than 70 years since we've seen any presence of this particular bird," said Anthony Erba, deputy forest supervisor at Chequamegon-Nicolet National Forest in Bayfield County, where the birds were seen. "When you come across something that unexpected ... it's like, 'Whoa, there it is.' "

The Kirtland's warbler has been on the list of federally endangered species since 1967, and was only known to nest in Michigan until last year, when about eight males were spotted in southcentral Wisconsin and two in Canada.

Conservation efforts in Michigan have raised the population of the warblers, which are now expanding outward, said Kim Grveles, assistant ornithologist at the Wisconsin Department of Natural Resources' Bureau of Endangered Resources.

About 1,697 males were reported in Michigan in 2007, Grveles said, an increase of about 200 from 2006.

The population increase is mostly credited to efforts from Michigan's Kirtland's Warbler Recovery Team, a 40-year-old partnership between private groups and state agencies to manage jack pine, the birds' preferred habitat, for the expansion and nesting of the species in the state, Grveles said.

"Even though we have habitat — and high-quality habitat — for the bird, we just didn't have much confidence that the bird would make that much of a jump to northern Wisconsin," Erba said. "But now we have confirmed presence of this bird in Wisconsin, and that's very exciting for us."

"We started last year doing formal surveys, because we knew that with a population growing like that, they would start dispersing," said Scott Posner, a wildlife biologist at Chequamegon-Nicolet National Forest's Washburn Ranger District.

Now that warblers have been confirmed in the region, the next step is to survey the area during the next breeding season to see if the migrating birds are coming back, and then ensure there is suitable habitat for them to breed in the forest, Posner said.

"After that, we will continue monitoring to see what's needed for them," Posner added.

The DNR is talking with land managers about possible management options to encourage the species to come to Wisconsin to breed, Grveles said.

Wisconsin has one of the best opportunities in the Midwest for these birds to increase its population, she added.

“Kirtland’s Nesting in WI This Year? 2007? Ontario, Too?” Answer: Yes (!)

That’s correct, Jay in Jasper. You’re on. It's Larry King Live…..here with Mr. Wood-Warbler tonight as we explore a fascinating explanation to your above question.

Let’s unravel the tale of the First Ever WI Nesting Record of Kirtland’s Warbler in 2007 {with the species AGAIN documented to be nesting this year in at least one WI county (Adams) and, perhaps another (Marinette) where they have also been seen in 2008; see below}:

The discovery of the first-ever Kirtland’s nest in WI begins on May 19, 2007. You’re a birder who is not only passionate, but have devoted your life to the environment as a career. Indeed, you are environmental consultant/wildlife biologist/birder Dean DiTommaso. On this fine spring day in central-southcentral WI, you discover three male Kirtland Warbler’s in a young red pine plantation in Adams County.

Did the intrigued DiTommaso call 911. No, but all banter aside, he did alert the WI DNR of his amazing gem of a discovery — and the Gold Rush was on, so to speak. During the ensuing days, under the guidance of the DNR, DiTomasso found three additional males at another site nearby. On June 2, 2007, the talented DiTommaso made his first observation of a female – thereby documenting the likely 2007 nesting occurrence (given that migrating or wayward Kirtland’s individuals, including females, would more likely be correctly judged as transients possibly moving through WI during May, but not necessarily staying to nest; by June, a sighting of a male and/or female Kirtland’s, or both, increases the chances that nesting is probable to confirmed, pending further monitoring).

Additional female Kirtland’s were seen on June 6 and 9 -- observations that eventually led to the discovery of a second and third nest in mid-June.

In total, during 2007, the DNR (with DiTomasso’s help), documented a total of at least eight singing male Kirtland’s, including three separate active nest sites in Wisconsin.

This year, 2008, the statewide total in WI is 10 males documented (Tom Schultz, personal correspondence, June 28, 2008). At least three female nests have been found. Two of these males were seen in Marinette County (the second County removed north of Green Bay, WI) and at least seven males have been color marked with leg bands (Noel Cutright, personal correspondence, June 29, 2008).

In turn, the perceptive reader may now ask: “Red pine is where the Kirtland’s was found in 2007? That’s interesting, given the Jack Pine is the historically preferred and obligate tree upon which this Federally Endangered wood-warbler usually depends.”

So what gives? Can we expect to conclude the two consecutive years (2007 and 2008) qualify Kirtland’s as an annual breeding species in WI (and, perhaps in Ontario where at least one pair was documented breeding in 2007)? (Sorry, I don’t yet have the status of whether Kirtland’s was again found nesting this year in Ontario.)

In addition, perhaps you’re wondering (like me)?:

Are Kirtland’s likely to spread the breeding ranges (in area) if they become annual breeders in WI and Ontario (beyond the six counties where they regularly nest in Michigan counties near Roscommon in the south-central south area of the state)?

The answer may potentially be “yes,” if the current coordinated Jack Pine planting plan meets its goals as executed by the DNR and the US Fish and Wildlife Service. Both of these agencies are combining their wildlife know-how and expertise with forest management efforts by the US Forest Service, Plum Creek Timber Company, and multiple WI County Forest Administrators (Trick, Grveles, DiTommaso, Robaidek, The Passenger Pigeon, Summer 2008).

Other potentially good news is that the above management efforts may help preserve and increase other bird species populations beyond the Kirtland’s. Such rare and declining species in the vicinity -- Vesper Sparrow, Brown Thrasher, and Black-Billed Cuckoo, to name just three species – are the most likely additional avian beneficiaries of prospective management schemes that could be executed to host the Kirtland’s in greater numbers.

So, the moral of the Great Kirtland’s Discovery of 2007? Get out there and bird.

Have fun doing so and Happy Bird Songing By Ear for those birding in the forest like I often do…..Daniel

Seven Species of High Sierra Mountain Wood-Warblers?

Answer:

Yes, the headline query is correct.

The question was prompted by Terese Frederick, one of my former students, who asked me recently if ".........there's more wood-warbler species nesting in the CA Sierra Nevada mountains (High Sierra Mountain Range), including the Yuba Pass area, Sierra County, 30 miles southwest of Truckee) than on the 'flats,' such as counties within the Bay Area?"

The brief answer* is that there's often MORE species annually nesting in the Bay Area than the nearby mountains 130-200 miles east of the Bay Area -- but that's only if you include the coastal counties of Marin and Sonoma.

These two counties constitute two of the Bay Area counties among nine (SF, San Mateo, Alameda, Contra Costa, Solano, Napa, Santa Clara)

In total, among the nine Bay Area counties, the typical RELIABLE annual nesting wood-warbler species include:
- YELLOW
- YELLOW-RUMPED (one of the four Audubon's subspecies)
- BLACK-THROATED GRAY
- WILSON'S
- ORANGE-CROWNED
- COMMON YELLOWTHROAT
- MACGILLIVRAY'S
- HERMIT
- YELLOW-BREASTED CHAT

"See, that's nine," I told Terese, and adding: "That's nine species in the Bay Area and ONLY seven species of nesting wood-warbler species during most breeding seasons in mountainous regions of the Sierras:

the above species minus the YELLOW-BREASTED CHAT and COMMON YELLOWTHROAT."

HOWEVER, in some mountainous areas within the Sierras, NASHVILLE WARBLER nests.

So, we have eight in some areas of the Sierras, I told Terese.

In sum:

Nine Bay Area wood-warbler nesting species vs. eight Sierran species.

The Bay Area wins over the Sierras by a mere one species.

Now, do you folks reading this entry KNOW HOW MANY wood-warbler species nest in the county within which you live?

Feel free to share your total with me as a "comment," below (by clicking on the comment text and entering your thoughts to me). (Please also feel free to vote at the quiz on the right.)

(* = More complex, it appears that N. PARULA may nest occasionally to regularly in Marin Co.
That makes 10 species for the greater Bay Area as nesting wood-warblers.)