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HEY! WHERE ARE THE HUMMINGBIRDS?

Last year (2004) was a great one for Ruby-throated Hummingbirds at Hilton Pond Center, as we finally went over the 200 mark for banded hummers in a season. Between 9 April and 28 September 2004 we captured 210 new ruby-throats, eclipsing our old record of 197 set in 1995; we also handled 29 returns from preceding years, including a sixth-year female banded 'way back in 1999. Over the winter we thought a lot about all those banded hummingbirds and bragged to various audiences that our local hummer population appeared to be in the rise. At the same time, however, we had a nagging fear in the back of our mind that this year--2005--might not turn out so well. Being in a southern coastal state, we were fully aware that last autumn was an exceptionally busy one for severe weather, with back-to-back-to-back-to-back hurricanes plowing through the Gulf States, Florida, Georgia, and/or the Carolinas--to say nothing of several near-hurricane tropical storms that arose in the same time frame. We couldn't help but think that such powerful, destructive events--which occurred on a near-continuous basis from 31 July through 10 October--could have significant impact on hummingbird migration, especially since these tiny birds would need to move across the Gulf of Mexico right at the peak of hurricane season. We were concerned that many ruby-throats fell victim to storms in the Gulf, so we weren't surprised this April when we started hearing from many folks who said "Hey! Where ARE the hummingbirds?"

All text & photos © Hilton Pond Center
2004 Hurricane graphic courtesy R. Hays Cummings' Tropical Weather Pages

Although the fall juxtaposition of hurricanes and hummingbird migration has existed for millennia, of course, it's been decades since so many strong storms occurred in one season; nonetheless, we always expect many resilient hummers to survive and return the next spring, but here at Hilton Pond in 2005 that doesn't seem to be the case. For years we've heard folks "cry wolf" in April, lamenting they didn't have as many hummers as they did in earlier years. We've historically advised those folks they probably DO have about the same number of birds and that they shouldn't judge their spring numbers based on their memory of hordes of birds at feeders during the preceding August and September. We typically consoled callers and E-mail correspondents that the population is always smaller in spring and that feeder activity is less because males are busy defending territories and females are spending long periods sitting on nests. Lots more birds would be apparent when the chicks fledge in late June and thereafter, we would explain, urging folks to just be patient. Despite such knowledge, however, many observers have been particularly insistent they have fewer hummers this spring than last and want to know two things: "Did all those hurricanes last year hurt my hummers?" and "Hey! Where ARE the hummingbirds?"

If we may backtrack a little, our personal fears of a possibly disastrous migration last fall began to dissipate in January 2005 when we observed and banded 15 Ruby-throats in Costa Rica (above right)--proof that at least SOME North American hummers made it to tropical wintering grounds. And then on 30 March we caught our first Hilton Pond hummer of 2005--our second-earliest bird ever. We took this as a sure sign things would go well, especially when we caught our third-earliest ruby-throat the very next day. But then there was a two-week lull before our next new ruby-throat on 14 April, followed by just one more bird three days later. After that, we caught a hummer on 5 May--which turned out to be LAST one so far in 2005! "Hey! Where ARE the hummingbirds."

That we've caught only five Ruby-throated Hummingbirds this year might not be all that surprising. After all, we do know that numbers are lower in spring than later in the year. But one of the valuable things about long-term projects AND being able to actually capture and band hummingbirds is that we get a reasonably accurate way to compare annual fluctuations in populations. Thus, when we examine the 22 years we've been studying Ruby-throated Hummingbirds at Hilton Pond (see Table 1 below) and reveal that on average we've banded 16.9 of them by 31 May, it becomes quite apparent that this year's tally of just FIVE by that date is exceedingly low. "Hey! Where ARE the hummingbirds?"

* = Bander was absent from Hilton Pond for part of field season (1984 banding began 27 July)
** = Averages do not include 2005 or the five previous years with partial field seasons

Even more ominous, when we look at our data and compare this year's results to the past eight, we find that more recently we've averaged 20.4 captures in April and May, even more than the 16.9 average over 22 years! In our judgment, this is pretty strong evidence there ARE fewer hummingbirds at Hilton Pond this year--evidence that should give pause to any folks who pooh-pooh backyard observers for continuing to ask "Hey! Where ARE the hummingbirds?"

In reality, some experienced observers report they don't see the dearth of hummingbirds this year that our analysis shows for Hilton Pond--or that many of our correspondents have inquired about. To help resolve this discrepancy, we conceived a survey and sent out word to various listservs and chat groups, inviting hummingbird watchers to surf onto the Web site for Operation RubyThroat: The Hummingbird Project and visit the Poll Page to vote on whether they thought Ruby-throated Hummingbirds were present this spring in larger, smaller, or equal numbers compared to years past. To determine if there might be a geographical difference in responses, we somewhat arbitrarily divided the U.S. and Canada into regions that included all states and provinces in which Ruby-throated Hummingbirds regularly occur as breeders or spring migrants. The ten regions were:

• Northeastern U.S.--Maine, New Hampshire, Vermont, Massachusetts, Connecticut, Rhode Island, New York
• North Atlantic U.S.--Pennsylvania, New Jersey, Delaware, Maryland
• South Atlantic U.S.--Virginia (including Washington DC), North Carolina, South Carolina, Georgia
• Gulf Coast U.S.--Florida, Alabama, Mississippi, Louisiana, Texas
• North Central U.S.--Michigan, Wisconsin, Minnesota, North Dakota, South Dakota, Montana, Iowa, Nebraska
• Central U.S.--West Virginia, Ohio, Indiana, Illinois
• South Central U.S.--Tennessee, Kentucky, Arkansas, Oklahoma, Kansas, Missouri
• Northeast Canada--Quebec, New Brunswick, Nova Scotia
• Central Canada--Ontario, Manitoba, Saskatchewan
• Western Canada--Alberta

Our on-line survey used a format provided for free by Pollhost.com and that allowed only one vote per computer. Instructions asked that respondents vote just for the region in which their respective sites were located. As noted on the sample ballot for the Northeastern U.S. (right), respondents selected one of three choices that described the number of ruby-throats seen at their feeders and flowers during the period 1 March through 31 May 2005, compared to previous springs. Multiple responses within each regional question were blocked by the survey software, so voters had to choose from ABOUT THE SAME, MORE, and FEWER.

We are first to admit the survey is "unscientific," but we believe the majority of respondents provided honest and accurate answers. Therefore, the results probably do give us a general overview of whether Ruby-throated Hummingbird numbers are up, down, or the same this year, and the survey results are quite interesting.

First of all, an embedded Web counter showed the hummingbird Poll Page was viewed 1350 times through 10 p.m. on 2 June 2005, when we compiled the data described below. Some of those hits were from individuals who visiting the poll page more than one time; 568 votes were cast--about 42% of the total views.

The smallest numbers of votes (see Table 2 above) came from the Canadian provinces, which is understandable; after all, some Ruby-throated Hummingbirds that breed in Canada may not even have arrived there yet. The biggest block of responses came from the South Atlantic U.S.--Virginia (including Washington DC), North Carolina, South Carolina, Georgia--which was the only region to report that significantly FEWER hummingbirds visiting backyard feeders and flowers in Spring 2005. This could explain why we've heard so many reports of low hummingbird numbers, since the South Atlantic region includes Hilton Pond Center and is the one in which we have the most personal contact with hummingbird enthusiasts.

Viewing the survey by percentages rather than actual votes is a bit easier to analyze. From Table 3 (above) we see that a sizeable percentage (22%) of 50 voters in the Gulf Coast states (Florida, Alabama, Mississippi, Louisiana, Texas) report they had MORE Ruby-throated Hummingbirds than usual this spring. Within the second largest geographical sampling (121 respondents from the Central U.S. region of West Virginia, Ohio, Indiana, Illinois), 12% of voters also thought they had MORE hummers, while ABOUT THE SAME and FEWER categories were almost equal at 45% and 43%, respectively.

Respondents from all regions combined said their Spring 2005 ruby-throats were SIGNIFICANTLY FEWER than normal (48%), with 43% reporting numbers ABOUT THE SAME. But if we remove tallies from the South Atlantic U.S.--a region leaning heavily toward FEWER hummingbirds this year--we find that almost half our respondents (49%) report hummer levels ABOUT THE SAME as always, and only 39% think they have FEWER.

So what does all this mean?

To summarize, of 568 total respondents in the U.S. and Canada, many (43%) think 2005 is pretty much a normal year for Ruby-throated Hummingbirds. But almost half (48%) believe their numbers to be FEWER than in past years, and a sizeable number of those folks are in South Atlantic states. If we accept the objectivity of the observers--and we believe, in general, that we can--hummingbird numbers are indeed down in various locations around the U.S. and Canada, but especially in the coastal Southeast.

We received numerous anecdotal reports that supplemented the statistics from our survey, and nationally those responses were mixed among MORE, FEWER, and ABOUT THE SAME. But many hummingbird enthusiasts from the Southeast bemoaned the near-absence of ruby-throats. Some observers, like Fred Houk of Chatham County NC, could even quantify the trend in noting that through 15 June last year he went through 25 pounds of sugar to make hummingbird feeder mix, while so far in 2005 he has used only ONE five-pound bag. Fred asks: "Hey! Where ARE the hummingbirds!"

Obviously, fewer Ruby-throated Hummingbirds are being observed at most locales in South Atlantic states. Some hummers undoubtedly are partaking of natural foods in woodlands far from human eyes, but we can't imagine that hummers would completely forsake feeders and backyard flowers. We can only conclude that--at least in the Carolinas, Virginia, and Georgia--there really ARE fewer hummingbirds than normal this spring. Perhaps ruby-throats from this region migrate at a time and/or along a route each autumn that made them particularly susceptible to the quadruple-whammy of hurricanes in the Gulf last fall. Or maybe most of our southeastern hummingbirds go to a specific Mexican or Central American wintering area that was affected negatively by deforestation or some other factor. Sometimes it's hard to understand cause-and-effect relationships in nature, but abnormally low numbers of ruby-throats this spring at many places in the Southeast at least tell us to investigate whether something unusual might be causing a diminished population.

To conclude, our Spring 2005 banding results clearly show there are significantly fewer Ruby-throated Hummingbirds this year than normal at Hilton Pond Center, but--to be honest--that doesn't alarm us nearly as much as what has happened since the current hummingbird season started back in late March. Across the Southeast--and much of the eastern U.S., for that matter--we've had unusually cool and wet weather. In fact, nearby Charlotte NC reports May 2005 as the chilliest one in 37 years and among the ten coolest in 129 years--all of which followed an April that was two degrees cooler than normal. We suspect our wet, windy, cool spring will cause a lower rate of nesting success in local hummingbirds, and if there are already small numbers of ruby-throats on hand to breed, it stands to reason that 2005 could end up being our worst hummer year in recent memory. We won't know until October, of course, after the breeding season and when the last migrant has departed, so we're just hopeful the population around Hilton Pond will rebound as summer progresses. Otherwise, when our usual peak banding time finally arrives in late August, we and others will still be asking: "Hey! Where ARE the hummingbirds?"

All text & photos © Hilton Pond Center

NOTE: We suspect some observers will disagree with the way others in their region responded to the hummingbird spring abundance survey, or with the conclusions we've drawn. But that's the way science works--always open to debate, differing perspectives, and new data. If you'd like to make a comment, please E-mail it to INFO. And while you're at it, send us some hummingbirds!