All, I had been having similar thoughts to Chris: can we quantify the impact of individual fallouts (or a series of fallouts) at a population level.
*However*, I worry quite a lot about using NFC or banding station counts to quantify this. Banding stations catch more migrating birds in inclement weather which forces them to the ground; NFC stations record more birds in low ceiling and overcast nights when birds are forced lower. Trying to account for these major weather effects will be a challenge. I have been thinking that BBS data may be a better course, at least for species like Scarlet Tanager, Rose-breasted Grosbeak, Indigo Bunting and Baltimore Oriole--all of which were hit hard in Texas. Best, Marshall On Wed, Jun 5, 2013 at 2:23 PM, Laura C. Gooch <lgo...@alum.mit.edu> wrote: > I checked with Julie Shieldcastle from Black Swamp Bird Observatory > (south shore of Lake Erie about 30 km east of Toledo). The numbers for > their Navarre banding station were actually above average for the spring, > contrary to my impression that they were low to moderate. Bill Evans > pointed out that the higher numbers this year are supported by his > listening station there: http://www.oldbird.org/Data/2013/ONWR/ONWR.htm > > Bill also pointed out that my call counts in Cleveland Heights are higher > than the detections at the listening station at Black Swamp this year. His > thought is that my station may get a concentration of birds attempting to > fly around Lake Erie, and also that artificial light at my suburban station > may be a factor. > > > Laura Gooch > Cleveland Heights, Ohio > > On 6/5/2013 8:38 AM, Laura Gooch wrote: > > I don't have enough years of data to say anything very > useful about night calls during migration here (east side of Cleveland, > Ohio). However, I do know that we had a very light spring banding season. > I believe that the banding season at Black Swamp Bird Observatory, on the > south shore of Lake Erie about 30 km east of Toledo (a few km east of > Magee Marsh), was also light to moderate. They have over 20 years of > banding data at BSBO, and I believe that they do note light years in > which winds seem to favor migrants staying farther west as they move > north. On the other hand, I know Mark Shieldcastle (research director at > BSBO) was concerned about mortality from the repeated periods of > unseasonably cold weather in the south central part of the country. > > I'm still analyzing my data for this spring. Most of what I've counted and > ID'd > so far is posted here: > > http://listeningup.wordpress.com/summary-of-night-flight-calls-detected/ > > > If some of you more experienced folks have a chance to take a look, I'm > curious how these numbers compare to what other stations detect. I'm > counting from 1/2 hours after sunset to 1/2 hour before sunset, which > will mean that I have few more hits than the 1 hour after/before > protocol, but this won't have much impact since I generally don't get > many hits in these periods. In addition, some of these nights still need > a second pass that will result in some adjustment of the numbers. I don't > expect the change to be more than 5% or so, mostly in the downward > direction as I eliminate a few possible hits that I previously flagged > for further examination. Unfortunately, I my ID efforts haven't caught up > to the days when significant warbler migration might be expected to begin. > > Laura Gooch > Cleveland Heights, Ohio > > --- On *Tue, 6/4/13, birde...@yahoo.com > <birde...@yahoo.com><birde...@yahoo.com> > * wrote: > > > From: birde...@yahoo.com <birde...@yahoo.com> <birde...@yahoo.com> > Subject: Re: [nfc-l] [nysbirds-l] Fwd: Minimal Migration or Population > Decline? > To: "Joan E. Collins" <joan.coll...@frontier.com><joan.coll...@frontier.com> > Cc: "Christopher T. Tessaglia-Hymes" <c...@cornell.edu> <c...@cornell.edu>, > "NYSBIRDS-L" <nysbird...@list.cornell.edu> <nysbird...@list.cornell.edu>, > "<NFC-L@cornell.edu> <NFC-L@cornell.edu>" > <NFC-L@cornell.edu><NFC-L@cornell.edu> > Date: Tuesday, June 4, 2013, 6:36 PM > > All, > > My delayed, or lack there of, sightings of many > migratory-Adirondack-breeding-species would fall in the same vein as what > everyone else is seeing. However, watching the Doppler radar patterns(which > I did over much of May) of spring migration species, show just what Chris > has mentioned...there were many nights when birds came up along the > Mississippi corridor due to that long lasting, and blocking weather pattern > through much of early May(or somewhere around that time!). And also as > Chris mentions, birds may have flown to the Great Lakes region(on favorable > winds)and finally found some westerlies to get them to eastern breeding > grounds. This could(?) explain why we missed so much in May. > Did we see higher (easterly) migration patterns around the Great > Lakes(Chicago, Cleveland, Buffalo?) > I hope we can get some more birder-input on this fascinating topic! > > Brian McAllister > Saranac Lake > > > On Jun 4, 2013, at 4:11 PM, "Joan E. Collins" > <joan.coll...@frontier.com<http://mc/compose?to=joan.coll...@frontier.com>> > wrote: > > Thank you for this interesting post Chris. This has been a dominate > topic of discussion among many birders in the Adirondacks. Sean O’Brien > and I have been talking every few days wondering what has happened to many > neotropical migrants this year. I mentioned the low numbers of Blackpoll > Warblers and Yellow-bellied Flycatchers on Whiteface Mountain in my earlier > post today, but numbers of most neotropical migrants appear way down. Sean > keeps remarking that there is no dawn chorus this year. Even my non-birder > husband has been noting the lack of birds this spring. Normally, you can’t > sleep past 4:30 a.m. in our house at this time of year because of the > remarkable dawn sounds outside our bedroom window, but it feels more like > late summer every morning with the lack of songs. I was aware of the > weather-related fallout on the Gulf Coast of Texas in April, and I had to > wonder, with so many birds too exhausted to be afraid of humans, how many > may have perished unseen over the Gulf? > > > > Migration seemed highly unusual this year. Normally, species like > Blue-headed Vireo would suddenly fill the forests overnight. This year, I > found ONE, and then a week went by and I found a second one, then several > days went by and they began to arrive in a trickle. Species were, for the > most part, late arriving and they trickled in. We have been waiting for > the forests to fill, but it hasn’t happened and it is now June 4th. In a > section of Massawepie Mire that is normally filled with breeding Canada > Warblers, we heard one on Saturday. It is definitely worrisome. > > > > As you mentioned, BBS surveys may help document the apparent population > declines. Thanks again for your thoughts about possible reasons for such > worrisome declines. I too, would be interested to hear the thoughts of > other birders on this topic. > > > > Joan Collins > > Long Lake, NY > > > > > > *From:* > bounce-98052797-13418...@list.cornell.edu<http://mc/compose?to=bounce-98052797-13418...@list.cornell.edu>[ > mailto:bounce-98052797-13418...@list.cornell.edu<http://mc/compose?to=bounce-98052797-13418...@list.cornell.edu>] > *On Behalf Of *Christopher T. Tessaglia-Hymes > *Sent:* Tuesday, June 04, 2013 12:18 PM > *To:* NYSBIRDS-L > *Subject:* [nysbirds-l] Fwd: Minimal Migration or Population Decline? > > > > Good afternoon! > > > > This morning, I sent the following email to NFC-L, the Night Flight Call > eList, and thought some on NYSbirds-L might find this of interest or have > some input. > > > > Sincerely, > > Chris T-H > > > > Begin forwarded message: > > > > *Date: *June 4, 2013 9:46:52 AM EDT > > *To: *NFC-L > <nf...@list.cornell.edu<http://mc/compose?to=nf...@list.cornell.edu> > > > > *Subject: Minimal Migration or Population Decline?* > > > > Good morning, > > > > I am curious to know if recording stations in the Northeast have > experienced, numerically – with respect to quantity of night flight calls, > a reduced number of migrants this spring as compared to past years. My > perception is that there was a noticeable lack of birds moving throughout > certain regions of the Northeast this spring. Conversely, did recording > stations elsewhere (perhaps in the mid-west) record higher numbers of > migrants this spring? > > > > On the ground, for example, I don't ever remember a year when I only heard > or saw 2-3 Blackpoll Warblers. Period. Usually, I would hear or see * > several* Blackpoll Warblers on any given day over the course of a few > days during the peak movement for this species. Of course, maybe a mass > die-off of Blackpoll Warblers and other migrants went unnoticed this past > fall or this spring, similar to the infamous mass die-off from 2-3 October > 2011 at the Laurel Mountain wind facility in West Virginia. See: > http://www.birdfellow.com/journal/2011/10/29/in_the_news_484_blackpoll_warblers_die_at_wind_farm. > Note: it is suggested these birds succumbed to exhaustion from becoming > trapped in the sphere of fog-reflected light produced by a lighted > substation, which was accidentally left on overnight at the facility, > rather than actual deaths caused by direct turbine strikes. > > > > I know there was a memorable weather-related fallout on the Gulf Coast of > Texas this past 25-27 April 2013. See: > http://www.texasbirdimages.com/home/2013-fallout---cameron-county/nueces-co-list---april-25-2013. > It makes me wonder if it is at all possible for unfortunately-timed severe > weather-related events, during key trans-Gulf crossings, to result in > population-wide declines of neotropical migrants. > > > > Or, is this just an anomalous year as a result of the negative phase of > the North Atlantic Oscillation, producing unfavorable conditions for > nocturnal movement of small passerines into the Northeast. In possible > scenarios like this, do boreal neotropical migrants favor an alternate > springtime route that may carry them North, up the Mississippi Flyway to a > point North of the Great Lakes, allowing them to then catch the prevailing > West wind in an Easterly direction to their breeding grounds? If such a > scenario were to play out, how do first spring individuals learn of these > routes? Do they follow the masses? > > > > Interestingly, I'm finding that the cuckoos seem most unaffected by minor > Northerly airflow at night (such as the night of 2-3 June). I'm sure their > body size and wing length have everything to do with the ability to migrate > into a headwind as compared to smaller passerines, such as warblers. Last > night, in calm to light winds, I recorded 7 different Black-billed Cuckoos > and a single Yellow-billed Cuckoo, plus a single Virginia Rail, one Alder > Flycatcher, one Swainson's Thrush, and a single Indigo Bunting. > > > > Unfortunately, I was not recording sooner this spring in Etna, NY, so > don't have a good comparison of this year to last year (for peak > migration); however, I did get out as much as possible to a migrant > stopover patch on most mornings (see the Hawthorn Orchard: > http://www.birds.cornell.edu/cayugabirdclub/hawthorn.htm and check eBird > for this site). My perception from daytime observation was a serious lack > of neotropical migrants, yet with a reasonable amount of resources (insect > larvae) for them to feed upon. This was one of the more memorable > springtimes for me, with respect to flowering trees. I don't recall a time > in the recent past of a springtime with the same amazingly full quantity of > flowers remaining on the trees for as long as they did, yet with so few > migrants. Though, perhaps in actuality there may have been fewer food > resources (insect larvae) available than in past years, due to the cooler > weather this spring (in the Northeast). > > > > If weather conditions correlate as closely to food resource availability > as is probably the case, perhaps the birds use weather-related cues to > avoid migration routes that may lead through regions with a dearth of food > resources as compared to routes through other regions with high food > resources. Or, perhaps there was a mass die-off in the Gulf this spring or > the Atlantic and/or Gulf last fall, or at nighttime lighted facilities on > unfortunately fog-enshrouded nights. It all seems so speculative without > looking at long-term population trends in different regions. I think it > will be interesting to watch for the comparative results from this year's > Breeding Bird Surveys to past Surveys and of Surveys to come in future > years, as well as the gradual accumulation of records in eBird. > > > > Thanks for any thoughts and input on this! > > > > Sincerely, > > Chris T-H > > > > -- > > Christopher T. Tessaglia-Hymes > > Field Applications Engineer > > Bioacoustics Research Program, Cornell Lab of Ornithology > > 159 Sapsucker Woods Road, Ithaca, New York 14850 > > W: 607-254-2418 M: 607-351-5740 F: 607-254-1132 > > http://www.birds.cornell.edu/brp > > > > > > -- > > Christopher T. Tessaglia-Hymes > > Field Applications Engineer > > Bioacoustics Research Program, Cornell Lab of Ornithology > > 159 Sapsucker Woods Road, Ithaca, New York 14850 > > W: 607-254-2418 M: 607-351-5740 F: 607-254-1132 > > http://www.birds.cornell.edu/brp > > > > -- > > *NYSbirds-L List Info:* > > Welcome and Basics <http://www.northeastbirding.com/NYSbirdsWELCOME> > > Rules and Information <http://www.northeastbirding.com/NYSbirdsRULES> > > Subscribe, Configuration and > Leave<http://www.northeastbirding.com/NYSbirdsSubscribeConfigurationLeave.htm> > > *Archives:* > > The Mail > Archive<http://www.mail-archive.com/nysbirds-l@cornell.edu/maillist.html> > > Surfbirds <http://www.surfbirds.com/birdingmail/Group/NYSBirds-L> > > BirdingOnThe.Net <http://birdingonthe.net/mailinglists/NYSB.html> > > *Please submit your observations to **eBird*<http://ebird.org/content/ebird/> > *!* > > -- > -- > *NFC-L List Info:* > Welcome and Basics <http://www.northeastbirding.com/NFC_WELCOME> > Rules and Information <http://www.northeastbirding.com/NFC_RULES> > Subscribe, Configuration and > Leave<http://www.northeastbirding.com/NFC-L_SubscribeConfigurationLeave.htm> > *Archives:* > The Mail Archive<http://www.mail-archive.com/nfc-l@cornell.edu/maillist.html> > Surfbirds <http://www.surfbirds.com/birdingmail/Group/NFC-L> > BirdingOnThe.Net <http://birdingonthe.net/mailinglists/NFCL.html> > *Please submit your observations to eBird<http://ebird.org/content/ebird/> > !* > -- > > -- > *NFC-L List Info:* > Welcome and Basics <http://www.northeastbirding.com/NFC_WELCOME> > Rules and Information <http://www.northeastbirding.com/NFC_RULES> > Subscribe, Configuration and > Leave<http://www.northeastbirding.com/NFC-L_SubscribeConfigurationLeave.htm> > *Archives:* > The Mail Archive<http://www.mail-archive.com/nfc-l@cornell.edu/maillist.html> > Surfbirds <http://www.surfbirds.com/birdingmail/Group/NFC-L> > BirdingOnThe.Net <http://birdingonthe.net/mailinglists/NFCL.html> > *Please submit your observations to eBird<http://ebird.org/content/ebird/> > !* > -- > > -- > *NFC-L List Info:* > Welcome and Basics <http://www.northeastbirding.com/NFC_WELCOME> > Rules and Information <http://www.northeastbirding.com/NFC_RULES> > Subscribe, Configuration and > Leave<http://www.northeastbirding.com/NFC-L_SubscribeConfigurationLeave.htm> > *Archives:* > The Mail Archive<http://www.mail-archive.com/nfc-l@cornell.edu/maillist.html> > Surfbirds <http://www.surfbirds.com/birdingmail/Group/NFC-L> > BirdingOnThe.Net <http://birdingonthe.net/mailinglists/NFCL.html> > *Please submit your observations to eBird<http://ebird.org/content/ebird/> > !* > -- > > > -- > *NFC-L List Info:* > Welcome and Basics <http://www.northeastbirding.com/NFC_WELCOME> > Rules and Information <http://www.northeastbirding.com/NFC_RULES> > Subscribe, Configuration and > Leave<http://www.northeastbirding.com/NFC-L_SubscribeConfigurationLeave.htm> > *Archives:* > The Mail Archive<http://www.mail-archive.com/nfc-l@cornell.edu/maillist.html> > Surfbirds <http://www.surfbirds.com/birdingmail/Group/NFC-L> > BirdingOnThe.Net <http://birdingonthe.net/mailinglists/NFCL.html> > *Please submit your observations to eBird<http://ebird.org/content/ebird/> > !* > -- > -- **************************** Marshall J. Iliff miliff AT aol.com West Roxbury, MA **************************** eBird/AKN Project Leader www.ebird.org www.avianknowledge.net Cornell Lab of Ornithology Ithaca, NY **************************** -- NFC-L List Info: http://www.NortheastBirding.com/NFC_WELCOME http://www.NortheastBirding.com/NFC_RULES http://www.NortheastBirding.com/NFC-L_SubscribeConfigurationLeave.htm ARCHIVES: 1) http://www.mail-archive.com/nfc-l@cornell.edu/maillist.html 2) http://www.surfbirds.com/birdingmail/Group/NFC-L 3) http://birdingonthe.net/mailinglists/NFCL.html Please submit your observations to eBird: http://ebird.org/content/ebird/ --
