By Sara Wright
Every time I think the Evening Grosbeaks are thinning out or even migrating en mass, they return. I have had a huge flock of these golden birds on my porch all winter and spring. Every morning the air is flooded with raucous finch bird song. According to many sources these beautiful birds are nomadic in southern areas but their presence here has been consistent. Irruptions (or rapid increases) of these birds in fall and winter are a common response to changing food supplies. Perhaps they stay around here because I feed them (as so many people do), but even with a stable food supply they will leave eventually. Western populations migrate to higher altitudes to breed sometime this spring and then return to the lowlands during the winter. In the Northeast, where I come from, the summer arrival of the grosbeaks is an event not to be missed because they migrate north to breed and are gone again within three months. In the last few years the bountiful flocks have been absent, having been replaced by a few breeding pairs. No one knows why Grosbeak numbers are in decline but apparently this downward trend holds for much of the US. While the pattern of decline is clear, the potential causes are murky unless one factors in the usual, Climate Change and insecticide use. I do know that these finches have adapted to having a regular supply of sunflower seed by growing a larger beak. Evening Grosbeaks interest me because they are an example of a bird that migrates in a limited way, (altitudinal) and one who also makes a long distance seasonal flight. Migration is the patterned movement from one place to another that occurs in birds, mammals, fish, reptiles, amphibians, insects and crustaceans. Migration may also occur at the cellular level. Migration can occur seasonally or just once in a lifetime. Birds like grosbeaks migrate to find food and to reproduce, but I can’t find any data on why these birds move from Abiquiu to higher altitudes to breed when there are extensive cottonwood canopies around here and a regular food supply, so there must be other unknown factors. It’s important to distinguish between birds that migrate seasonally for food and reproduction from those who are forced to leave one place for another because of human induced habitat loss, and Climate Change. Is it possible that one of the reasons the grosbeaks move to the mountainous ranges is to escape the heat? Like scientists, I have been intrigued by migration because we know so little about how birds and animals know what they know, and because, unfortunately, whatever capabilities animals have developed over millennia are also being interrupted in ways that we can barely comprehend. Multitudes of studies indicate that 1,800 of the 10,000 remaining bird migrating species probably use a wide variety of mechanisms to navigate, including the stars, the sun, olfactory (chemical) cues, internal circadian rhythms that change in response to the seasons, and Earth's magnetic field. Controversial field theory may also offer an explanation. But the point is, we don’t really know. The mysteries of bird migration continue to haunt me with questions I can’t answer. Here are a few examples of the ways bird migration has changed over the years: 1. Evening grosbeak migration patterns are shifting. 2. Some Canadian geese migrate seasonally; others remain in some states year-round. 3. Lesser black-backed gulls began appearing regularly in the New Jersey area in the 1970s, and are now fairly common winter visitors. 4. Sandhill cranes that used to migrate to Florida for the winter have stable winter populations in the state of Tennessee, and this year we had whole flocks of these birds who spent the winter here rather than moving further south. 5. Not all Rufous hummingbirds migrate to the tropics for the winter. Some are now flying south to areas like Alabama and Florida to remain there for the winter. 6. Barn swallows habitually migrated to South America during the winter but at present they also nest there in addition to moving north to breed. We may not know how migration works, but we do know the patterns of migration are changing and that Climate Change is a reality. My fervent hope is that somehow most species, who are all our “elders” – humans, after all have only been around for 200,000 years - (plants for 450 million years, animals for 350 million years) - may possess strategies that we can’t even imagine to survive the damage that we have brought upon all living things, including ourselves.
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Republished from 3/19
By Sara Wright I have developed a fascination and a deep respect for the Great Tailed Grackle as a result of making regular visits to Walmart. I began feeding these birds bread crumbs this winter because I like them so much and because I wanted to observe these clever characters hopping about dodging automobiles and people who apparently don’t have much use for them. Some always hang out on the roof with the fake owls that were put there to scare them. I wonder how many people have actually looked at the Great Tailed Grackle because both sexes are quite stunning. The male is glossy black with an ecclesiastical purple iridescence. He has a long, keel-shaped tail, massive bill and yellow eyes. The female is about half the size of the male and looks as if she’s been dipped in brown oil; she has a smaller keel shaped tail. The visual characteristic that stands out the most to me is the brilliance of those bright yellow eyes. These birds radiate intelligence! And, in fact, studies that have been done on these birds reveal that they are adept at problem solving (even from a human point of view). For example, the Grackles problem-solving power was tested by posing glass cylinders full of water with bits of food floating just outside the birds reach. To grab the morsels, the birds had to drop in pebbles to raise the water levels. After a number of trials most of the Grackles figured out that dropping pebbles into the water raised the water level so they could feed. They also learned that it was usually more efficient to use heavy pebbles to reach the snack, but if provided with too large stones the birds turned back to small pebbles to reach their goal. Another test done had even more dramatic results. Silver and gold tubes of food were presented to the grackles but only the gold tubes had peanuts and bread in them. The Grackles immediately chose the gold tubes, but when the food was placed in silver tubes the birds instantly chose them. These tests reveal not only problem solving ability but also the birds’ flexibility in terms of learning. Its important to note that Grackles outperformed three species in the crow family (Corvids). This desert-adapted bird doesn’t need much beyond food, trees, water, and its own wits for survival. Once confined to Central America, the species began moving north 200 years ago, and now covers an immense region from northwestern Venezuela up to southern Canada. In 1900, the northern limits of its range barely extended into Texas; by the end of the century it had nested in at least 14 states and was reported in 21 states and 3 Canadian provinces. This explosive growth occurred mainly after 1960 and coincided with human-induced habitat changes such as irrigation and urbanization. Where people have gone, Great-tailed Grackles have followed: you can find them in both agricultural and urban settings from sea level to 7,500 feet that provide open foraging areas, a water source, and trees or hedgerows. In rural areas, look for grackles pecking for seeds in feedlots, farmyards, and newly planted fields, and following tractors to feed on flying insects and exposed worms. In town, grackles forage in parks, neighborhood lawns, and at dumps. More natural habitats include chaparral and second-growth forest. Great-tailed Grackles are loud, social birds that can form flocks numbering in the tens of thousands. Each morning small groups disperse to feed in open fields and urban areas, often foraging with cowbirds and other blackbirds, then return to roosting sites at dusk. This evening routine includes a nonstop cacophony of whistles, squeals, and rattles as birds settle in for the night. As near as I can tell Grackles forage almost anywhere and will eat almost anything. What this says to me is that these kinds of birds have learned to co – habit with humans in very ingenious ways that must include being able to deal with pesticides. During the last month (March) I have noted that there are fewer Grackles hanging around the parking lot. One reason for this absence may be that during the day some birds are moving into more rural areas to feed. In addition to country foraging and prior to actual nesting, both males and females begin to collect material for the nest site about four weeks before actual breeding begins in April. Nesting occurs in colonies of a few to thousands, with the nests often placed close together. The actual nest construction is done after this period of “gathering,” which although not mentioned in any of the sources I consulted, must be related to the mating process. The females choose the nest site, and often “borrow” nest-building materials from other females. The nest is made of grass, twigs, reeds, and mud and is woven by the female in about 5 days in a tree, shrub, or hidden in marshland vegetation placed anywhere from 3 to 30 feet off the ground or water. Nest size varies from four inches across to 13 inches deep. The female will lay 4 to 7 eggs that are pale greenish brown with blotches. The young are ready to fledge in a month. Mother is responsible for brooding and feeding. During this period some male Grackles may guard the nest while the female forages. In contrast some others may pair with a second female during this time leaving the female to manage on her own. Curiously, fewer male than female nestlings survive. Adult male survival may also be lower than adult female survival, which would result in a female-biased adult sex ratio. Although there is considerable overlap in the distribution of the three species, the Common Grackle occurs throughout the eastern United States and Canada, the Great-tailed Grackle is found in the Midwest and south/western United States, and the Boat-tailed Grackle is confined to Florida and coastal areas of the Gulf states and the eastern United States. The Grackle is protected by the Migratory Bird Treaty Act, which as far as I can tell, means practically nothing. People routinely haze, shoot, or use pesticides to eliminate these birds but their numbers continue to increase. In this time of great uncertainty due to Climate Change and continued overuse of lethal pesticides I can’t help but feel reassured that some non – human species will survive, and whenever I spend time with the Walmart birds I feel flickers of hope rising. I am already looking forward to seeing the Great Tailed Grackles once again flooding the Walmart parking in Espanola by the middle of May. The timing couldn’t have been worse. I entered the garden focused on photographing flowers, so I was totally unprepared to see the monarch fluttering around helplessly almost hitting the cement as it attempted to recover its ability to become airborne. Instinctively, I turned away before I realized that what I had just witnessed was the trauma that this butterfly was experiencing after just having been tagged.
This organization’s hope was that some guide or kid in Mexico would find the tagged DEAD body of this monarch somewhere on the ground after the butterfly completed its journey from Maine to its winter stopover in Mexico. I found this perspective bizarre because finding a dead monarch means that the butterfly will not winter over to finish his/her reproductive journey north in the spring. Not a success story for the monarch. What possible agenda lies behind these tagging operations that brag about monarchs that die in their wintering grounds is a mystery to me. That the tagged butterfly I witnessed was suffering from distress was painfully obvious even as I heard the tagging woman say “get another, this one wasn’t graceful enough”. Did I mention that the sequence was being filmed by one of the major television networks? Take two. I buried myself in the flowers, but my heart was pounding, and I was distracted, and this is how I managed to clash with butterfly tagging practices for a second time. I ran into a man with a stiff nylon net who was in the process of capturing another victim in its depths. Though he turned away I knew exactly what was happening having witnessed what occurs when a butterfly is caught in this manner. The insect becomes frantic. After being pursued and trapped the butterfly was now moments away from tagging distress. I glanced at the hapless creature pinned down by the wings. Groaning involuntarily, I sensed the trauma the poor butterfly was experiencing, and quickly exited the garden. Done for the day. Although I was a member of this conservation organization this naturalist/ethologist couldn’t sanction a practice which even encouraged and included allowing children to tag. Didn’t anyone think about how the butterfly might experience this practice? After expressing my opinion to those in charge, I deliberately avoided witnessing Monarch capture and tagging. This year only one monarch was tagged at the summer festival, or so I was told while I was busy volunteering at the bird table in mid – August. A few nylon bagged caterpillars were munching on a nearby milkweed clump. That day while participating in a bird walk on my break, I saw one monarch in the field. When I returned to the garden about ten days later to check on the flowers (I love the pollinator garden), I was happy to see and photograph bees and wasps and the few monarchs that were fluttering around the Mexican Sunflowers. This time the caterpillars were gone, and a few chrysalises were zipped into the nylon bags to protect the inhabitants from parasites until eventual emergence, or death. I knew from personal experience that OE (disease) was only one of the problems and that some chrysalises would not hatch anyway. Hopefully the few that did would not hatch during a time when no one was present to release the butterfly before it damaged its wings. Only about 10 percent of these insects make it to adulthood. I was also keenly aware that the monarch count had plummeted 22 percent just since last year. Depending on the source consulted 90 – 97 percent of these butterflies are missing in action; the species is approaching extinction despite laudable attempts to ‘save’ it. The word extinction requires explanation. This is a process that occurs over an unspecified period, but once the existing population has declined beyond a certain point the dye has been cast. Sources vary but most agree that once 75 percent of the population has vanished, extinction is imminent. Because I am a naturalist and aware of what is happening overall, I choose to focus my attention on letting nature choose how much milkweed to grow in my wildflower field and appreciating the monarchs I find in all stages of their lives while we still have them. Spend some time watching a caterpillar eat through a milkweed leaf, turn himself into a ‘J’ to pupate. Look carefully at the exquisite chrysalis tipped in gold leaf; watch it darken and become translucent as the butterfly prepares to split the capsule. Sit with the emerging butterfly as her wings dry and she prepares for first flight. Last year I was present when the monarch I had been watching began pumping fluid into her wings and then fluttering and flapping them before sailing away into a cobalt blue sky… Nature’s Grace. I won’t forget. Yesterday when I visited the garden to take pictures of flowers it never occurred to me that monarchs were going to be tagged while I was there, or that I would be unfortunate enough to witness the process by accident. Of course, they were being tagged because this is what this organization does, I realized on my way home. These are the monarchs that will be making the 2000-mile migration to Mexico. I was upset with myself. How naïve, how stupid I was not to make the connection between the time of year and tagging but then I realized that because I had taken every precaution not to be present for any part of this process and thus far had been successful why would it have occurred to me at all? Today I learned that everyone is invited to witness butterfly tagging twice a week during the month of September. Efforts to publicize the ‘rightness’ of tagging are being stepped up. Several people agreed with my assessment, namely that tagging creates trauma for the insect – and the idea that this practice may interfere with the butterfly’s ability to survive the 2000-mile journey, winter over successfully and then fly north to reproduce in the spring. To my knowledge no one else had openly expressed their personal views to those in charge of the organization. However, some folks have come to talk with me. Most of us know that trauma weakens any organism’s immune system making it more vulnerable. I also have friends who are biologists or scientists who agree that we have no way of knowing how tagging effects the butterfly or its ability to migrate successfully, and that even a small tag can create an imbalance in flight. The underlying assumption (now hardened into ‘truth’) is that attaching an object to the hind wing of a butterfly that weighs less than half a gram with a tag that weighs 02 percent of the butterfly’s weight is placed close enough to the butterfly’s center so as not to disrupt flight. What I had just witnessed suggested otherwise. When tagging began in 1992 scientists wanted to gain more insight monarch migration and decline. Monarchs caught the public’s attention, becoming a cultural icon for ‘save the species’ groups. Monarch Watch and Xerces (there are many others) began their research. Data accumulated as hypotheses came and went. Thirty plus years later we have masses of detailed information, but we have failed to stop the monarch’s steep decline. As previously stated, the monarchs who hatch in September are the ones that make the long arduous journey to the central mountains of Mexico. The obvious threats of habitat loss – our disappearing forests, grasslands, clean water and air, the continued use of pesticides/herbicides, poisoned waters are compounded by the extremes that are being brought on by our changing climate. In Maine this tropical summer of floods and fog has given us a taste of what’s to come. In southern climates it’s fires and intolerable heat. I do appreciate one aspect of this long -term research project. It has alerted some people to the plight of a disappearing butterfly and hopefully that will lead to folks seeing the ‘bigger picture’. We desperately need humans to comprehend the enormity of our earth crisis and how it is affecting what’s left of our wildlife, not to mention ourselves. Many people who have lawns are exchanging them for wildflower and pollinator gardens. These actions may assist other species to survive but unfortunately, I think it is too late for the monarchs. While engaged in my research last year I learned from one reputable source that handling a butterfly removes butterfly powder. The loss of this precious wing ‘dust’ protects the butterfly from aerial predation. Other researchers are quick to point out that they have learned a lot about the flyways the monarchs use, the problems associated with raising captive monarchs, diseases that affect the species, the fact that migratory behavior is remarkably sensitive to genetic and environmental changes, that even brief exposure to unnatural conditions even late in development may be enough to disrupt flight orientation (like bagging?). Compiling data gained from gathering and quantifying information seems to be more about what humans want to learn about these insects in general than caring about the lives of actual butterflies. From my point of view butterfly survival also requires asking what it means when a tagged monarch experiences trauma and then is found dead before it has completed its life cycle. Of course, there are a host of possibilities, but I find it disturbing that not one academic source addresses this issue. I do not speak Monarch but as an ethologist (a person who studies animal behavior in the wild) I certainly pay close attention to behavior and butterfly tagging does creates trauma for the insect; that much is obvious. Why no one mentions tagging as another reason our monarchs may be in steep decline is an important question that deserves attention. Western science is supposed to be value free which of course is an illusion. However, the necessity of appearing to remain value free forces those who believe that a butterfly has feelings is dismissed as a person who is anthropomorphizing. Attributing trees and plants, animals, birds, frogs, lizards, and insects with feelings is projecting human qualities onto animals according to this way of thinking. In conservative science, the old story, non- human beings don’t experience feelings of pain etc. have personal relationships or live lives that may or may not intersect with those of humans, let alone communicate with other species. If an academic or person like me is radical enough to disagree with this perspective severe criticism and ostracizing, follow. Conservative western science refuses to acknowledge that the new sciences tell us a very different story, one in which all nature is alive and sentient. In this scenario trees, animals, birds, insects etc. experience fear and other emotions that are unique to each species but share a commonality with humans because we are all part of the same whole. Anyone who has ever had a personal relationship with an animal or plant knows this whether s/he admits this or not Advocating for sentience originally developed out of my naturalist’s life experiences; research came later. I pay close attention to any encounters with non -human beings and draw conclusions from actual encounters as I did with the monarch (even when those conclusions conflict with prevailing theories or popular beliefs). That human caught butterflies feel fright and anxiety is obvious to anyone who pays attention. The bottom line is that when it comes to tagging butterflies, we do not know what the consequences are. Is it worth repeating that the tagged monarchs recovered in the mountains of central Mexico are all dead and their natural life cycle has been disrupted permanently? Tagging creates trauma and stress that may be one more reason the monarch butterfly is in steep decline. Postscript: Andy Davis of Monarchscinece.org is a research scientist at the School of Ecology in the University of Georgia. Andy has been studying monarchs, especially their amazing migration since 1997, and is the editor-in-chief of a scientific journal devoted specifically to animal migration. Andy is the author or coauthor of 35+ scientific studies on monarch biology. Andy has this to say about tagging: “We already know that the stressors monarchs face during migration are immense - like cars, loss of nectar, storms, etc. What if the weight of the tags, even if it is incredibly minor, is causing monarchs to burn slightly more energy during flight every day, so that they arrive in Mexico with not quite enough fat to survive the winter. Or, maybe the minor weight of the tag causes the monarchs to not flap as efficiently as it would have normally. Or, maybe the tags are leading to slightly, but chronically-elevated metabolic rates. Or, for all we know, there is a behavioral issue at play here - maybe the white tags cause the tagged monarchs to be shunned by their untagged friends, and the tagged monarchs are then prevented from joining the rest of the monarchs in the safe tree clusters. Who knows? The point is, we really don't have any data on the effect of tags to monarch physiology, flight mechanics, or behavior to say anything about this, but, given this new evidence (about increasing mortality at the winter sites), maybe it’s time for scientists to take up this issue”. Andy Davis is a research scientist at the Odum School of Ecology in the University of Georgia. Andy has been studying monarchs, especially their amazing migration since 1997, and is the editor-in-chief of a scientific journal devoted specifically to animal migration. Andy is the author or coauthor of 35+ scientific studies on monarch biology. This morning I watched aghast as Mr. Rufous hit the window and fell to the ground. Rushing out to give him sugar water, I was so relieved to see him recover his wits and fly towards his cottonwood bower on his own. A very close call. Rufous, an iridescent coppery jewel arrived here on June 22 and his mate – just as beautiful in her less dramatic emerald and rust attire, came with him. My other resident hummingbirds (black chin, and broadtail) all seemed to be cooperating as they visited my two feeders. I wondered how Rufous and his wife would fit in so I have been keeping a sharp eye on hummingbird cooperation dynamics. Five weeks have gone by since their arrival, and this couple is staying to raise a family. It is true that this pugnacious little hummingbird can throw a wrench into cooperation but I have been pleasantly surprised to see this male and female sipping nectar with other birds sitting on neighboring perches. Could it be that the broadtail and black chin social dynamic has rubbed off on Mr. and Mrs. Rufous? I have no way of knowing but it does seem that they are more willing to compromise than most others I have known. Some days, of course, Mr. Rufous hovers above the feeders and making sudden aggressive dives scaring the others away with his high pitched squeaks and buzzing - but only for a few moments. Usually he lets the others return to share quite companionably. Mrs. Rufous seems very cooperative and she has taken to visiting the nastursiums, scarlet runner beans, fiery salvia, deep rose and scarlet penstemon and the pot that holds my bee, butterfly, and hummingbird friendly wildflower mixture that Iren gave me last spring. Apparently, the territories that the male and female rufous hummingbirds “defend” are somewhat different. Males hover over the primary food source(s) while the females extend their ranges further afield choosing less dense wildflower meadows. But this year, except for my little pot garden there are few wildflowers beyond the fence where I do not water, so choices, at least here, are limited. And Mrs. Rufous does not hog these flowers. Rufous hummingbirds are small with a short tail with mighty flight skills that allow them to travel 2000 miles from Mexico to as far north as Alaska for breeding in the western states. This migration can take place from as early as May to August in New Mexico, and some stop along the way to raise their families. They follow the wildflower season throughout the rocky mountain area. During their long migrations, they make a clockwise circuit of western North America each year moving up the Pacific Coast in late winter and spring, reaching Washington and British Columbia by May. As early as July they may start south again, traveling down the chain of the Rocky Mountains. The adult male has a slender bill, white breast, a rusty face, flanks and tail with a startlingly beautiful orange-red throat patch or gorget. Some males have some green on back and/or crown. The female has green, white, some iridescent orange and a dark tail with white tips. The female is slightly larger than the male and has longer wings. As many of us know they feed on nectar from flowers using a long extendable tongue or capture insects on the wing. These birds require frequent feeding while active during the day and go into a state of torpor at night to conserve energy. Because of their small size, they are vulnerable to insect-eating birds and animals. Most breeding habitats are open areas, mountainsides and forest edges in western North America and the Pacific Northwest. The female builds a nest in a tree or shrub and raises her brood of two chicks alone. The offspring are ready for flight in about three weeks. Surveys show continuing declines in rufous numbers during recent decades. Because they rely on finding the right conditions in so many different habitats at just the right seasons during the year, this hummingbird is especially vulnerable to the effects of climate change. These iridescent "flower birds," were considered gifts from the gods by Indigenous peoples. In Peru and other South American countries, naturalists have cataloged over three hundred species, and it is believed that not all have been discovered yet. The rain forests of South America were probably where hummingbirds first evolved (co-evolved) with flowers. I like to imagine that hummingbirds once sipped the life-giving nectar, leaving behind a pollinated forest before flying away, their burnished colors shimmering in a primal world of sunlight… |
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