Hi all,
I must vehemently disagree that we have "no control over the wintering grounds." In fact, American consumers have a lot of control, as it is our purchasing decisions that are fueling a very large portion of deforestation in Latin America. A whole lot of acreage is being lost to supply this country with cheap coffee and cheap beef - acreage that could otherwise support (more) sustainable development and less destructive agriculture. Drinking "certified bird-friendly" coffee (legitimately shade-grown, organic, and Fair Trade) is probably the absolute easiest way we can all make a difference each and every day without changing our lifestyle. It's not going to save the world, but it's a place to start, and research has shown that a well-managed, truly shade-grown (not some rows of pesticide-coated banana trees in the middle) coffee plantations are nearly as valuable as undeveloped rainforest to a wide range of resident and migratory species.
Let me put it (overly) bluntly: If you're sipping cheap, sun-grown coffee on your way to buy a fast-food hamburger, you might as well just shoot that oriole that's at your feeders. I know I'll get grief for that analogy, but the rate of deforestation to fuel our cheap caffeine addiction is just that destructive.
More info on coffee, with lots of links for more info:
Meanwhile, on a more local note, I believe the main reason for the lack of oriole observations this spring is directly related to the weather and tree phenology (timing). While other factors (population decline, forest maturation, development, etc) are all real and have a very real impact on oriole populations, those factors do not usually result in such obvious year-to-year variation. This year, we saw an incredibly early growing season, with flowering, leaf-out, and the related insect emergence well ahead of schedule in most places. Weather in the last few days of April and the first week of May was often unfavorable for nocturnal migration (orioles, like most Neotropical migrants), delaying the arrival of quite a few species. When they - such as orioles - arrived, natural food sources (which are almost always preferred to supplemental bird feeding station offerings) were widely available and birds of many species (orioles, Scarlet Tanagers, and catbirds in particular) simply didn't need the helping hand. Good for the birds, but not necessarily good for the birders. Locally (in my yard in Pownal and here at the store in Freeport) oriole visits to our feeders have been very few and far between. However, the local birds are still present and accounted for - such as the pair that nests three yards over from our house and fly over woods to get to our feeders. I don't want to belittle the declines of Neotropical migrants - which is far too real and significant - but "detection biases" seem to be playing a signficant role in people's observations - or lackthereof. Fewer birds at feeders, more widespread natural food sources (limiting concentrations and visibility), and more well-developed leaves to obscure birds are all helping produce what a biologist would term a "false negative" or "non-detection."
-Derek (currently enjoying a nice steaming cup of Birds & Beans Coffee on another unseasonably cool morning).
-Derek
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Jeannette and Derek Lovitch
Freeport Wild Bird Supply
541 Route One, Suite 10
Freeport, ME 04032
Ph: (207)865-6000/Fax: (207)865-6069
www.freeportwildbirdsupply.com
Visit our E-store http://store.freeportwildbirdsupply.com/
Jeannette and Derek Lovitch
Freeport Wild Bird Supply
541 Route One, Suite 10
Freeport, ME 04032
Ph: (207)865-6000/Fax: (207)865-6069
www.freeportwildbirdsupply.com
Visit our E-store http://store.freeportwildbirdsupply.com/
From: Bruce Bartrug <bbartrug@gmail.com>
To: Hank & Linda Nevins <fridge6@tidewater.net>; maine-birds@googlegroups.com
Sent: Thursday, June 7, 2012 10:26 AM
Subject: Re: [Maine-birds] Re: Baltimore orioles
When I first visited Costa Rica, I walk up the road from the pension where I was staying toward the Monteverde Cloud Forest while waiting for lunch. Among the first birds I noticed were hairy woodpecker, cedar waxwing, Baltimore oriole, and dusky-capped flycatcher (a Myiarchus flycatcher that breeds in SE Arizona). I wanted to ask, "Where the heck am I?" Kentucky and golden-winged warblers were also common here.
Many of our neotropical migrants winter in southern Mexico and Central America, although the hairy woodpecker and waxwing are resident in these mountains. This is not only a small area physically compared to their breeding grounds in North America, but many of these migrants prefer middle and high elevations in the mountainous areas. This preference again cuts down the physical size of their wintering area.
This elevation in Central American just happens to be optimum for growing coffee and grass for cattle and horse ranches, and forests here have been cut for that purpose since the middle of the 20th Century. It was the reason there was a noticeable decline in migrant birds beginning in the 70's. Wood thrushes, Tennessee warblers, olive-sided flycatchers, and perhaps Baltimore orioles were once much more common than today.
No control over the wintering grounds? Maybe, but the US has no stellar record of championing social justice in this part of the world either. And in a way has contributed to the current situation. Conservation and social justice go hand in hand. In the latter part of the last century I even gave presentations about this issue. Today since the terrorist activity, I'd probably have a police record :). Not a topic for this forum, but if you'd like to hear more write me off-line.
One way we can help is to visit neotropical bird lodges and spend some money there. What a boring chore, huh? :) Here's an example:
http://www.brucebartrug.com/oil/single-gallery/1055763 . You need to click the little button at the bottom of the image, click here.
Cheers,
BAB
On Thu, Jun 7, 2012 at 7:21 AM, Hank & Linda Nevins <fridge6@tidewater.net> wrote:--
Thank you, Bruce! Hearing this from someone nearby makes me feel that at least I'm not doing anything to cause the orioles not to come - but your possible cause is much scarier as we have no control over their wintering sites. Thanks again!----- Original Message -----From: Bruce BartrugSent: Wednesday, June 06, 2012 8:23 AMSubject: Re: [Maine-birds] Re: Baltimore oriolesTo gauge the number of orioles breeding in Maine, the best source would the compilations of the annual Breeding Bird Survey. There are several BBS routes in Maine, and the results of these would show a decline if one exists. Seeing large quantities of orioles, or lack of same, during migration isn't an indication of relative abundance. That said, I have noticed a decline in this species in Beautiful Downtown Nobleboro as well. Ten years ago we would have two pairs singing and visiting oranges. This year we didn't put any oranges out because I haven't heard one singing.
One must remember orioles winter in Central America, a rather small area which has had some significant changes in land use in the last 50 or 60 years. If you're looking for reasons for a general decline, this would be the place to start.
BAB
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