Jamaica Days

“Bob, mi see a different bird a mi house yesterday.”

Fairweather is a 40-year-old Jamaican employed as a security guard at Green Castle Estate. He is also one of two locals my wife and I have been training as bird guides. So his statement got my full attention.

“A different bird? What do you mean? What was it?

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A handsome, Fox Sparrow-sized finch, the Greater Antillean Bullfinch is commonly encountered in forests and thick underbrush. (Photo by Bob Lockett)

"O mon, it was a pretty pretty bird. Mi tink it a Rose-breasted Grosbeak”

“Really!” Tell me more! What did you see?”

“It was in a tree outside mi window. Mi saw dis bird wid a black back an white below, wid a nice red breast.”

“How about the bill?”

“It was big big, like a Bullfinch. Here di picture in di book. Mi neva seen dis bird before.”

Fairweather showed us the photo of an adult male Rose-breasted Grosbeak in Ann Hayes-Sutton’s Photographic Field Guide to the Birds of Jamaica. Dwayne, the other trainee, chimed in: “Whoa! Nice bird!” We talked about the rarity of Rose-breasted Grosbeaks on the island (most migrate across the Gulf of Mexico to Yucatan, avoiding the West Indies) and we congratulated him on his sighting.

Reflecting on the episode later that day, we realized that our bird guide training had crossed an important threshold: both trainees had gone beyond an interest in the possible moneymaking aspects of being a guide; they had now progressed to a genuine enthusiasm for birds and birding. We’d like to claim that we were responsible for their expanded worldview, but the reality is that these gentlemen developed this perspective largely on their own.

The two of us are Peace Corps Volunteers from Portland, Oregon, members of the growing “50+” segment of enrollees. We’ve been assigned to the Environment Sector here in Jamaica for 26 months, March 2009-May 2011. Our new home is on a stretch of the north shore that, due to the vagaries of geography and highway design, remains one of the most unspoiled and least-visited coastal portions of the island. Robins Bay in St. Mary Parish is a small, sprawling community of perhaps 1800 souls nestled against the flank of the 1600-acre Green Castle Estate.

Green Castle Estate has had a succession of owners and a history that stretches back to the pre-Columbian Taino culture. Until recently, it was a farm dedicated to the cultivation of one or another of Jamaica’s signature crops: papaya (done in by the ringspot virus of the 1990’s), coconut (severely impacted by Lethal Yellowing disease), sugar cane, pimento (the local name for allspice) and cacao. Lessees still engage in agricultural pursuits as varied as shade house orchid raising, organic coconut oil production, and the raising of beef cattle. Despite—or in some cases because of—this  agricultural use, the estatelands constitute a rich mosaic of habitats hosting a wealth of birds, insects, and plants.

The nonprofit Greencastle Tropical Study Center, to which Adrienne is assigned, is the environmental conscience of the Estate, tasked with conserving its cultural and natural heritage. GTSC’s charge is to provide a ridge-to-reef field station for research and teaching, and to promote tourism activities in a manner that fosters sustainable economic and community development. Since our interest and expertise is birding, we’re doing what we can to put Green Castle on the birding map. To that end, we’ve recommended placement of ads in appropriate publications, hosted BirdLife Jamaica (the local birding club), networked with island and international birders, worked on trail development, undertaken the training of bird guides, and advised on habitat conservation and restoration.

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Jamaican Mangos, like the one pictured above, are large and aggressive hummingbirds. They dominate Green Castle's feeders, bullying the competing streamertails. (Photo by Wayne Sutherland)

Upon our arrival, we learned that a list of birds recorded on the property already existed. It was based in large part on observations made by two Humboldt State University grad students who conducted point counts on the Estate in 2006. Over the last year, we’ve been fortunate to add another 24 species. The Estate checklist, currently 122, includes 21 of the island’s 27 endemics (28, if you split the Streamertails), plus another 7 Caribbean endemics. Given Green Castle’s low elevation, it’s surprising that the avifauna is so rich. Of course, “rich” is relative; a mainland tropical tract of comparable size might host 2 or 3 times as many species.

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The Jamaican Elaenia is one of two elaenias found on the island. We are fortunate that both are distinctively marked; indeed Jamaican birds provide very few identification challenges. (Photo by Mike Whiteside)

The number of Jamaican endemics is related to the island’s isolation from the nearest mainland, but also testimony to the length of that isolation. Although the geological history of the Caribbean is complex and poorly understood, it’s very possible that Jamaica never had a mainland connection. Many species may have “island hopped” to Jamaica from Nicaragua/Honduras during times of low sea levels, when additional islands helped to bridge the distance. James Bond, the famous West Indies ornithologist, theorized that much of Jamaica’s (and the other West Indian islands’) avifauna arrived from Central America before the Pliocene era joining of Central and South America (Bond 1948). He believed that at least some of the ancestral Central American genera and species may have succumbed to competition with colonizing South American avifauna. This would account for the lack of close mainland relatives of such West Indian specialties as the Todys, Palmchats, etc. Whatever their origins, Jamaica has been graced with some unique and truly spectacular bird species.

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Potoos are fairly common on the island and can be reliably encountered at Green Castle Estate, where they are often quite approachable as they perch on fence posts after dark. (Photo by Bob Lockett)

We’ve discovered that Green Castle Estate is one of the better places to see some of these unique bird species. Yellow-shouldered Grassquits, Jamaican Elaenias, and Jamaican Becards are fairly common residents, and Jamaican Lizard-Cuckoos and Ring-tailed Pigeons are here, though elusive. The breathy “hooa” of Jamaican Owls is heard nightly during the winter months, and it takes exceptionally bad luck to miss one of the resident Northern Potoos when out after dark.

Jamaican Mangos, Vireos, Spindalis, Euphonias, Orioles, Todies, and Woodpeckers are ridiculously common, as are “Red-billed” Streamertails, White-chinned Thrushes, and Sad and Rufous-tailed flycatchers. Mangrove Cuckoos, despite their name, are found in any brushy habitat. The spring and summer months are punctuated by the incessant “John Chewitt!” songs of Black-whiskered Vireos, which give way in the evening to the “Gimme Me Bit” calls of Antillean Nighthawks. In addition to those treats that one can find on the estate, Ecclesdown Road—an essential stop for those hoping to see Jamaica’s highland endemics—is less than 90 minutes away.

Eight species of pigeon are found on Green Castle (Ringed-tailed and White-crowned pigeons; White-winged, Zenaida, Caribbean, and Mourning doves; Common Ground-Dove; and Ruddy Quail-Dove). Olive-throated Parakeets (common), Green-rumped Parrotlets (fairly common) and Yellow-billed Parrots (vagrant) are the local parrot family representatives.

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In addition to the array of endemics and Caribbean species found on the island, Jamaica serves as a migratory stopover and wintering grounds for many neo-tropical migrants. Black-throated Blue Warbler (above) is among the most common wintering Parulids along with American Redstart, Common Yellowthroat, and Cape May and Prairie warblers. (Photo by Bob Lockett)

Sixteen species of warblers have been recorded on the property; certainly a few more must occur in passage. One of our best sightings to date was that of a basic plumaged Blue Grosbeak last October; even more surprising, the same or another individual was found and photographed by us March 1 of this year. According to Ann Hayne-Sutton’s guide (Hayne-Sutton et al. 2009), Blue Grosbeak is a rare vagrant with just one record since 2006. Is it possible that this bird overwintered?

One of the benefits of our long-term residence is that we are afforded the luxury of observing local birds through the seasons. As a result, we gain more than just a brief glimpse into their lives.

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Tiny forest sprites, it's difficult not to think of Jamaican Todies as "cute." Until one learns their characteristic "tschik" calls, they are easily overlooked as they sit quietly in forest undergrowth. (Photo by Bob Lockett)

For two Pacific Northwest residents, living with Caribbean birds is fascinating and a constant source of wonder. Waking to the harsh squawks of Olive-throated Parakeets, the mournful song of Zenaida Doves, and the electrical buzzing of Bananaquits is a treat. We’ve learned that Smooth-billed Anis have a social life as rich as that of many parrots, with mutual grooming and closely-huddled roosting, though they perhaps lack the inquisitive intelligence of psittacines. We’ve discovered that Todies (aka Rasta Bird or Robin Redbreast) are best located by their scolding “tschik” calls since their greenish plumage allows them to blend perfectly with the forest undergrowth. We’ve also come to appreciate why the locals refer to Mangrove Cuckoos as “Rain Birds.” This species seems to call much more frequently before, during, and just after rain.

It’s been an adventure to spend this past year  in Robins Bay and, as with all adventures, there have been low moments and high. Slogging through summer’s oppressive heat, losing the “current” (electricity) for more than a day at a time, traveling in grossly over-packed buses, and attempting to understand a new culture have been real challenges. Our Peace Corps work has had its ups and downs as well. But we know we are making a difference in our community when the kids ask us if we’re running another environmental summer camp and we can see progress with our other projects such as bird guide training. Hearing the sweet whistled call of Jamaican Orioles; swimming in the warm, clear waters of the Caribbean; enjoying the richness and variety of tropical fruits; and birding the forested trails of Green Castle Estate have been among the best parts of this half-completed adventure.

You can find out more about the area’s birds and other facets of local life by following our blogs on the Green Castle Estate’s website: http://blog.gcjamaica.com/.

Sources cited:

Bond, James, 1948, Origin of the Bird Fauna of the West Indies, Wilson Bulletin, Vol. 60, No. 4, p. 207-229.

Haynes-Sutton, Ann, Audrey Downer & Robert Sutton, 2009, A Photographic Guide to the Birds of Jamaica, Princeton University Press, Princeton

Can We Trust the Colors We See?

Over recent weeks frequent visitors to this site will have noticed a lack of new posts to the our online journal. During this period our efforts have been focused on gathering and organizing photos into galleries that will eventually appear online. Steve Mlodinow, who has been a regular contributor to this journal, is among those who are supplying us with photos for our future online galleries. While sorting and loading some of his images, I found a picture of an interesting female Eurasian Green-winged Teal (see below) in a collection of photos that he took during a May 2009 visit to Adak Island in the Aleutian Island chain off the mainland of southwest Alaska.

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Note the apparent difference in color between the blue inner most secondaries of the left wing and the green inner secondaries on the right wing. This female Eurasian Green-winged Teal was photographed at Adak Island, Alaska in May 2009 (photo by Steve Mlodinow).

Though a bit out of focus, the image above serves to remind us that the colors we think we are seeing can be both subjective and/or misleading. At first glance, the mis-matched colors in the wings of this female teal are a bit confusing. However, there is a rather simple explanation for why one wing appears to have a green speculum while the speculum on the opposite wing looks blue.

First, it is important to understand how the colors we see in a bird’s plumage are produced. Plumage coloration is produced one of two ways. Like human skin, most bird feathers contain pigments that give each feather color. These pigments result in the blacks, browns, reds, oranges, and yellows that we see in the plumages of many bird species (www.ducks.org/DU_Magazine 2007). Though changes in light angle and intensity will cause some variation in the lightness or darkness of the color our brain perceives, the actual feather color is to some degree constant.

It should be noted that feather wear and sun bleaching often cause pigmented feathers to fade as they age. Most of us have seen gulls with bleached-out flight feathers in the summer months. At that time of year, the flight feathers of a gull are nearly a full year old. Most birds, including gulls, replace their flight feathers just once a year during a prebasic molt that usually occurs during the summer and fall months. During this molt, retained flight feathers will generally show worn and tattered edges and appear much paler than newly grown feathers in the same feather tract. In some cases, the old feathers will be so worn that they appear to be little more than quills.

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This first-cycle Glaucous Gull, photographed at San Francisco, California on 7 May 2009, offers a classic example of a gull with plumage (particularly flight feathers) that is both very worn and sun-bleached. Its flight feathers would have been acquired during late summer or early fall of 2008, meaning that they were nearly a year old at the time this image was captured and due to be replaced during its next prebasic molt. (photo by Dave Irons)

In addition to colors that result from pigmentation, we also perceive colors that are created by light refracting off of the minute structural components of a feather (www.birds.cornell.edu/allaboutbirds). These structural characteristics cause light to refract (bend or change direction) in ways that, depending on the angle of incoming (incident) light and our viewing angle, may cause us to see several colors reflected from a single feather. Colors resulting from this type of refraction are often iridescent. The gorget color of a hummingbird and the speculum (wing patch) color of many dabbling ducks result from light refraction and not pigmentation. Depending on the reflection of incident light, such feathers may appear highly colorful or black. When the feathers look black, little or no light is being reflected off the feather surface back to our eyes. Instead the light is being absorbed (www.birds.cornell.edu/allaboutbirds). When we are seeing an array of highly iridescent colors, lots of light is being reflected off of the feather surface back to our eyes.

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More often than not, when one sees a Double-crested Cormorant, its plumage looks mostly black or very dark brown. However, when lighting conditions and the viewing angle are just right, as was the case when this cormorant was photographed at Estero San Jose, Baja California Sur, Mexico on 8 January 2009, various green, bronze, and even purplish hues become apparent. (photo by Dave Irons)

After all this explanation, we are still left to wonder, “why are the specula of the teal in the picture above two different colors?” It would seem highly unlikely that there would be a difference in pigmentation in the two wings. More importantly, it has been determined that blue coloration in feathers results from light being scattered by small barbs in the feather rather than pigmentation (http://www.birds.cornell.edu/allaboutbirds). It is also pretty safe to assume that the structural characteristics of the individual wing feathers should be the same in both wings. What is different in this case is that the wings are not being held at the same exact angle in relation to the light source . Also, our viewing angle of the two wings is slightly different as well. These two factors cause light to refract through the feather and reflect back to eyes in ways that cause us to see color differences between the two wing patches.

As you look at birds and try to quantify plumage colors, it is important to recognize that lighting conditions and viewing angle play a significant role in producing the colors your brain tells you that you are seeing. Further, if colors appear iridescent, be assured that what you are seeing is the product of refraction and not actual pigment in the feathers.

Literature Cited:

http://www.birds.cornell.edu/allaboutbirds/studying/feathers/color/document_view

http://www.ducks.org/DU_Magazine/DUMagazineNovemberDecember2007