Mockingbirds Redux; Bumblebees

By in Insects, Species Accounts, Vocalizations

Judging from the emails I received about the last post on mimic thrushes, a lot of people share my enthusiasm for Northern Mockingbirds. A Northern Mockingbird on the Colby College campus helps my friend Ron Joseph with his workouts. Ron likes to walk laps on the track surrounding the football field. A male mockingbird keeps Ron amused with an amazing song repertoire. Ron has heard the following mimicked songs and calls: Red-shouldered Hawk, Killdeer, American Kestrel, Great Crested Flycatcher, Eastern Phoebe, Blue Jay, Black-capped Chickadee, Tufted Titmouse, Carolina Wren, American Robin, Wood Thrush, European Starling, Field Sparrow, Scarlet Tanager (chick-burr notes) and several other songs that are more difficult to identify. That is a virtuoso!

In this, we will venture into another group of flying animals, the bumblebees. These insects are important plant pollinators. Their life cycle is a fascinating one.

We are currently at a major event in the bumblebee year. I’ll bet you saw some large bumblebees in May, continuing into this month. These bumblebees were few and far between. Now, we are starting to see  smaller bumble bees appearing. In a few weeks, even smaller bumblebees will appear.

So, what is going on with these different-sized bumblebees? No, we are not dealing with the emergence of different species of different sizes. Within a species, we see three distinct size-classes of bumblebees.

Like many other members of the insect Order Hymenoptera (bees, wasps, ants), bumblebees are colonial. A large group of related individuals live and work together to maintain the colony.

Note that bird colonies are quite different. A bird colony consists of many Cliff Swallows, Atlantic Puffins, penguins or, once, Passenger Pigeons nesting in a restricted area. Every individual is engaged in reproduction and most are not close relatives of each other. In insects, very few members of a colony reproduce but are all related. The others support the reproductive individuals, forgoing their own reproduction but getting some of their genes into the next generation by helping to raise sisters or brothers.

To understand a bumblebee colony, let’s start in the winter. The only member of a bumblebee colony that will survive the winter is the queen. She mated in the fall before entering hibernation so she is ready to lay fertile eggs in the spring.

Time is of the essence for the queen as she must find a cavity to begin a new colony. A bumblebee queen does not dig her own nest cavity but rather uses an old rodent burrow, an opening at the base of a tussock of grass and even a human-made cavity.

After emergence, the queen gathers pollen and nectar from the few flowering plants that are available. Within her cavity, she first constructs a wax-cup and then lines it with the pollen and nectar she has been collecting. Then, she lays eggs. Once the larvae hatch from the eggs, they gobble up the pollen that their thoughtful mother set aside for them. Within a couple of weeks, the larvae pupate and then emerge as workers, non-reproductive females. We are just starting to see the workers now.

The workers defend the colony and collect the pollen and nectar for the larvae. Released from her pollen-collecting duties, the queen can become an egg-laying machine. Workers roll off the assembly line.

In late summer, the queen lays fertilized eggs that will give rise to new queens. Some of her eggs are not fertilized and they develop into males. Males are usually smaller than the workers. The males’ job is to fertilize the newly born queens so they can overwinter and be ready to go the next spring to start a new colony. The old queen, the workers and the males will not survive the winter.

We only have 17 species of bumble bees in the state so getting a handle on them is not daunting. Here’s a great resource for their identification: https://www.fs.fed.us/wildflowers/pollinators/documents/BumbleBeeGuideEast2011.pdf

Northern Mockingbirds and Other Mimics

By in Vocalizations

I am delighted that at least three pairs of Northern Mockingbirds are nesting in my neighborhood in Waterville. When we moved to Maine in 1990, this species was essentially absent from central Maine. The species has been spreading north over the past quarter of a century. Mockingbirds are quite common in North Carolina where I grew up and it’s nice to have these old acquaintances around in Maine.

I checked out the Northern Mockingbird page on the Maine Bird Atlas website (https://ebird.org/atlasme/map/normoc) to see the current distribution of mockingbirds in the state. In central Maine, the birds show a very patchy distribution. Their presence is associated with urban areas. I see islands of mockingbirds around Lewiston/Auburn, Augusta, Waterville, Orono/Old Town and Dover-Foxcroft. Mockingbirds don’t tend to come to feeders very often. I think the presence of mockingbirds in towns and cities has more to do with habitat alteration. Mockingbirds like the sparsely vegetated yards of suburban environments and avoid forested landscapes.

Northern Mockingbirds belong to the mimic-thrush family, the Mimidae. The name comes from the ability of these birds to mimic the vocalizations of other birds. We have three mimic-thrushes in the state (Gray Catbird, Brown Thrasher and Northern Mockingbird). The three species are easy to tell apart by eye, as a glance at your field guide will demonstrate. Telling them apart by voice is as easy as one, two, three. Gray Catbirds sing the various songs of their repertoire just once before moving on to the next. Brown Thrashers sing their songs in pairs and Northern Mockingbirds sing each song thrice..

Northern Mockingbirds are the most skilled mimics of these three species.. It’s amazing to hear a single bird sing spot-on versions of Blue Jay, Red-shouldered Hawk, Tufted Titmouse, Eastern Towhee, Killdeer, Northern Cardinal, White-breasted Nuthatch and others in quick succession.

Sometimes a mockingbird will mimic the song of a bird not found locally. For instance, a Northern Mockingbird in Austin, Texas was heard imitating a Green Jay, whose closest population is along the Rio Grande, over 300 miles away. Perhaps the mockingbird had spent time in the Rio Grande region or perhaps it learned the song from other mockingbirds who passed it northward over time.

A male Northern Mockingbird may have over 150 songs in its repertoire. The repertoire may change over time and generally gets larger with age.

So, what is the advantage of such virtuosic mimicry? It seems clear that mockingbirds are not trying to deceive other birds. Rather, the size and diversity of a male’s repertoire is probably important in attracting mates. Females are impressed by a male with a large repertoire.

The starling family also has many species that are gifted mimics. The introduced European Starling is a remarkable mimic. Pet starlings can be readily taught to mimic human speech. From DNA analysis, we know that the starling and mimic thrush families are closely related so their ability to mimic other sounds likely first appeared in the common ancestor of the two families.

Vocal mimicry is surprisingly widespread in the songbirds. Over 20% of the roughly 5,000 songbirds are known to mimic other birds. Males in the majority of these species must learn their species-specific song from their father or other tutor so the ability to mimic is not surprising.

Sometimes, young males learn the wrong song. Examples in North America include a Vesper Sparrow singing the song of a Bewick’s Wren and a Chestnut-sided Warbler singing the song of an Indigo Bunting. Of course, their plumage and song don’t match so birds singing the wrong song have no chance of acquiring a mate.

Blue Jays can be a bit devious in their mimicry. Some do a wonderful imitation of a Red-shouldered Hawk. That vocalization causes birds at a feeder to flee for their lives, giving the Blue Jay the feeder to itself.

Physiological Adaptations in Migrating Birds

By in Migration, Physiology, Weather

The spring migration is coming to an end. The arrival of Black-billed Cuckoos, Blackpoll Warblers, Salt Marsh Sparrows and Nelson Sparrow’s will mark the end of the spectacle.

Spring migration is a wonderful event. We marvel at the sudden appearance of birds, dressed in their breeding finery with males singing lustily. The spring migration lifts our spirits.

Understanding the physiological demands of migration makes the spring migration even more astounding. Birds are the edgiest of creatures. By that I mean that meeting energy demands is more difficult for birds, particularly small birds, than for any other animals.

Birds and mammals are the only two groups of animals that are truly warm-blooded or endothermic in the terminology of physiologist. Endotherms maintain a constant body temperature in the face of varying environmental temperature.

Endothermy is a tremendous advantage, allowing such animals to find food and avoid predators in harsh temperatures. Living life at a faster pace promotes learning; birds and mammals are the most intelligent of all animals.

The cost of endothermy is great. Heat lost has to equal heat produced. On colder days, the internal furnace has to be stoked at significant cost. Compare a mammal and bird of the same size and you find that the bird’s thermostat is set a bit higher than the mammal’s thermostat. The fire of life burns brightest in the birds.

Small birds have a tougher time making ends meet because of the cruelty of geometry. Heat is lost across the surface of a bird’s body. Replacing that lost heat is the job of organelles called mitochondria that are found in every cell in the body. The amount of heat produced is therefore proportional to the volume of a bird.

Let’s consider a couple of cubes, one with a length of 2 inches and one with a length of four inches. Each side of the smaller cube has an area of 4 square inches. Six sides give a total surface of 24 square inches. Its volume is 2 x 2 x 2 = 8 cubic inches. The ratio of surface-to-volume is 24/8 = 3. The same calculations for the bigger cube yield a surface-to-volume ratio of 96/64 = 1.5.

You can see how a small bird is at a real disadvantage. It has a relatively large surface area where heat is a lost and a meager volume in which heat is produced. An African elephant does just fine outside in a Minnesota zoo in the winter because its surface-to-volume ratio is so small. A hummingbird would have no chance in such cold weather.

As you read this column, your body is idling at its Basal Metabolic Rate (BMR_. If you were to exert yourself as hard as you can,  doubling your BMR is the best you can do. For birds, flight is ridiculously expensive. A flying bird has to increase its BMR up to 23 times!

To fuel that elevated metabolism, a bird has to pack on fuel. Fats are the fuel of choice. A gram of fat has twice the calories of a gram of carbohydrate or protein. The breakdown of fats also produces more water than other types of fuel.

The amount of fuel carried is determined by the length of a migratory leg. For Ruby-throated Hummingbirds crossing the Gulf of Mexico, two grams of fat need to be carried in addition to the lean body weight of three grams to provide enough oomph to make landfall in Mississippi.

Prior to migration, the gut of a bird enlarges to allow rapid digestion and absorption of food. But during the migration, the bird shuts down its gut to save energy. When a bird lands after a migratory leg, it takes a day or two to get the gut working again.

Given the energetic demands of migration, it is no surprise that birds wait for favorable winds to continue their migration.

Climate Change and Spring Arrival Dates

By in Migration, Weather

Spring migration is peaking now. Many warblers and thrushes are now arriving. Some are passage migrants, on their way to more northerly breeding territories, while others will find places to nest here in Maine.

Diet strongly influences when spring migrants will arrive in Maine. Birds like Red-winged Blackbirds, Common Grackles and sparrows that rely on seeds are among the first birds to arrive. Vireos, tanagers and warblers are leaf-gleaning insectivores, meaning they gobble up caterpillars feeding on tender leaves of plants. There is great risk in arriving in Maine before the leaves appear because caterpillar abundance is low.

Many naturalists like to keep track of the unfolding of spring. They track the night when the first spring peepers are calling, the first appearance of blackflies, the first appearance of leaves of various plants, the first flowers of Trillium, blueberries and other plants. This study of the effect of climate on recurring natural events is called phenology.

We know that the earth’s climate is warming. The past five years were the warmest on record. These upward trend in temperature is associated with increased carbon dioxide in the atmosphere. Carbon dioxide emissions have been increasing steadily since the Industrial Revolution began about 1850..

Phenological records indicate that many natural events are occurring earlier now than they did in the past, consistent with warmer winters and earlier springs in modern times.

For birds, we have some intriguing long-term records of spring-time arrivals in the northeastern United States. Chris Butler analyzed first-arrival dates from the records of  the Cayuga Bird Club in upstate New York and the Worcester County Ornithological Society in Massachusetts for the period 1903 to 1993. He showed that all 103 species of migratory species are arriving early in the period of 1951-1993 than they did in the period of 1903-1950. Butler found that short-distance migrants like Yellow-rumped Warblers and Common Grackles are arriving about 11 days earlier now. Long-distance migrants that winter in the Caribbean, Central America or South America are arriving only about four days earlier. He suggested that short-distance migrants are more responsive to local temperatures since they are already in North America. There is no way that a Bobolink wintering in Argentina can know whether a Maine spring is warmer or colder than normal.

Vitale and Schlesinger analyzed the spring-time arrival dates of 44 species in Dutchess County, New York over the period of 1885-2008. They found earlier arrival dates for 40 of those species, with the average change being 11.6 days per century.

What do we know about changing arrival dates for Maine birds? We do not have a continuous record of arrival dates as seen for the New York and Massachusetts regions. However, the short-lived Maine Ornithological Society did publish the Journal of the Maine Ornithological Society (JMOD) from 1899 through 1911. The journal included bird records, including first-arrival dates.

From 1994 through 2017, I coordinated a citizen-science project to track the first arrival of Maine migratory breeding birds. We therefore have a way to compare average arrival dates at the beginning of the 20th century with the late 20th/early 21st century.

My students harvested all of the spring-time arrival dates from the JMOS for comparison to our modern records. We had sufficient data to analyze 78 species of migratory breeding birds.

The results stand in stark contrast to the results from the Massachusetts and New York regions. In Maine, only nine of 78 species arrived earlier in the 1994-2017 period than in 1899-1911. Twenty-two species are arriving later now! For 47 species, we found no difference in average arrival dates.

Why do we see such different results in Maine? I suspect the observers who contributed sightings to the JMOS were out in the field more often than the contributors in my arrival date project so hence were likely to detect migrants earlier in the season.

Bird Rehabilitation and Avian Haven

By in Bird Conservation, Conservation

Building on the momentum from Earth Day, we should think about the direct and indirect ways that human activities imperil birds. Window collisions, car collisions and predation by pet cats that are allowed to go outside exact a significant toll on our birds. Birds may ingest lead weights and jigs lost by anglers or lead pellets from shot gun shells. The list goes on.

Collisions, cat attacks and lead ingestion may injure rather than kill birds. Bird rehabilitation centers offer such injured birds a fighting chance. Bird rehabbers are heroes.

In this column, I want to highlight the good work of Avian Haven in Freedom, Maine as an example of the positive impact of bird rehabbers. We have a handful of rehab clinics in the state but I’m concentrating on Avian Haven because I have first-hand experience with that facility.

Avian Haven was established in 1999 by my friends Diane Winn and Marc Payne. Diane was a colleague of mine at Colby College where she was a Professor of Psychology. After her retirement, she and Marc dedicated their time and energy to bird rehabilitation. I think Diane is busier now than when she was a Colby professor!

Avian Haven was in the national news in January. The Great Black Hawk that spent a portion of the winter in Deering Park in Portland suffered severe frostbite in January. The bird was captured and taken to Avian Haven. Despite their best efforts, the tropical hawk could not be saved.

However, Avian Haven has many success stories to tell. In 2018, 2,900 birds were admitted to the clinic. Since they opened, Avian Haven has treated more than 26,000 birds. Many of these were birds that had suffered either collisions or cat bites. Some of course succumbed to their wounds. Cat bites are particularly insidious because of the bacterial infections that often result if the bird’s skin is punctured. Antibiotics must be administered soon after a cat bite.

Keeping cats indoors is obviously the most effective way to reduce predation on birds. However, an effective way to allow your cat to be outside but reduce the threat to birds is to fit your cat with a stylish cat bib (https://catgoods.com//). The bib prevents a cat from pouncing.

Summer is a busy time for Avian Haven. About 38% of the birds taken in are orphan birds that must be hand-fed until they fledge.

In 2018, 130 species were handled by Avian Haven. The most common was Herring Gull with 216 cases followed by American Robin, Mourning Dove, Eastern Phoebe, Barred Owl and American Crow.

Avian Haven continues to grow. They now have 15 buildings where mending birds can be housed. One building is big enough to allow Bald Eagles and other raptors to fly. Other buildings are equipped with pools to make diving birds right at home.

Some birds that enter the clinic can be saved but their injuries prevent them from being released into the wild. Those birds may be put to work as foster parents, eagerly adopting  chicks that are brought into the clinic. These birds include a Mallard and a Rock Pigeon, named Mr. Pumper because of his enthusiastic feeding of chicks.Avian Haven is a working facility and tours are not available. Avian Haven is for the public but not open to the public. Diane and Marc are joined on the staff by a Rehabilitation Manager, a Physical Plant Manager and a Staff Veterinarian along with a ton of dedicated volunteers and interns. They also have a pool of 200 volunteer drivers who traverse the state, bringing injured birds to Avian Haven. These drivers often work in relays, pony-express style, to get an injured bird to Avian Haven. Don Fournier led the way by delivering 788 birds, driving almost 34,000 miles. Check this great facility out at www.avianhaven.org and learn how you can help.

Boreal Forest Initiative

By in Conservation

Earth Day (April 22) serves as a reminder to all of us to redouble our efforts at minimizing our impacts on this globe and do what we can to help the millions of species with which we share this earth.

Climate change represents one of the most dramatic changes our world is experiencing. The timing of various biological and meteorological events attests to our altered climate. Ice-out on our lakes is earlier now as well as the first appearance of leaves on many of our trees, the first flowers of many plants, the first singing of spring peepers and the spring-time arrival of migratory breeding birds.

We are also seeing the northward expansion of the ranges of many mobile species. Turkey Vultures, Red-bellied Woodpeckers, Tufted Titmice and Carolina Wrens are all well established in Maine now but were rarities 40 years ago.

Climate change, habitat fragmentation and pollution collectively challenge the survival and successful reproduction of many birds. Birdlife International finds that 1,469 of the roughly 10,000 bird species are in danger of extinction. That’s one of very seven species!

Partners in Flight estimates that songbird abundance in North America has declined by more than a billion birds since 1970.

Based on the first-year results of Maine Breeding Bird Atlas, compared with the first atlas (1978-1983), it seems clear that nesting of Bank Swallows, Cliff Swallows and Tree Swallow has fallen precipitously. All catch insects on the wing. Entomologists are concerned about declining insect populations. Fewer insects may lead to fewer insect-eating birds.

Frankly, we have done a poor job of looking out for nature in the Lower 48 species. But there is a large and important habitat in North America that is still largely intact, the North American Boreal Forest (hereafter, the NABF).

This biome stretches from Alaska to Newfoundland, occupying 1.5 billion acres. The NABF has experienced no industrial development and human populations are limited. Within this biome, one can find extensive bogs and fens, large lakes and rivers, and alpine habitats as patches in the thick coniferous forest.  Wildlife biologists estimate between one and three billion birds nest in the NABF each year. It’s no wonder some have bestowed the title of “North America’s bird nursery” on the NABF.

Although Maine and other northern states have pockets of boreal forest, Alaska is the only state in the contiguous NABF. Most of the forest is Canadian.

Over 300 species of birds nest in the NABF, representing nearly 50 families. The forest is particularly important for 151 species that have at least a quarter of their breeding population there; 35 of those species have at least 80% of their breeding population in the NABF. The latter includes Solitary Sandpiper, Boreal Chickadee, Palm Warbler and Lincoln’s Sparrow.

Many birds in the NABF move out of the region to the south for the winter. Some like Surf Scoters or Dark-eyed Juncos may go no further south than Maine while others like Blackpoll Warbler winter in South America.

Because migratory birds connect different areas, bird conservation requires attention to all portions of the range of a species. For the NABF, the Boreal Songbird Initiative (http://borealbirds.org) is playing a leadership role in conservation of this area.

The chief scientist on the Boreal Songbird Initiative is Dr. Jeff Wells. Jeff grew up in Bangor, went to college at UM-Farmington and earned this doctorate at Cornell, working at the Cornell Lab or Ornithology. He is currently based in Hallowell.

To conserve the present diversity of the NABF, no more than 50% can be lost to forestry and other uses by indigenous people. That seems attainable.

Climate change is the more serious threat. Reducing carbon emissions everywhere will help as well as targeting and conserving so-called climate refuges in the NABF that will likely offer relatively cool habitats in the future as the climate continues to warm.  Check out the Boreal Song Initiative website for more details of this important conservation effort.

Ornithology and Citizen Science

By in Bird Conservation, Reproduction

They’re coming! Spring migration has begun, none too soon for most of us. The first Turkey Vultures, Killdeer, Red-winged Blackbirds and Common Grackles are widely reported in Maine over a month ago and each day adds more species.

If you want to find when you should expect to see the first arrivals of a particular species, I invite you to use a webtool I created for that very purpose: https://hobbes.colby.edu/arrival/

This webtool was made possible by the contributions of over 400 birders who contributed spring arrival dates for 105 species of birds from 1994 to 2017.

You can use the webtool to see how the arrival dates for a particular species have changed over the 24-year period as well as the impacts of spring-time temperatures.

This project is a great example of the power of citizen science, relying on the contributions of many volunteers for a common goal.

Many examples of powerful projects accomplished through citizen science are chronicled in a recent book by Mary Ellen Hannibal titled Citizen Scientist: Searching for Heroes and Hope in an Age of Extinction.

We know that many species are under assault because of human impacts. Habitat destruction, accelerated release of carbon dioxide and other greenhouse gases into the atmosphere and pollution are but some of the insults humans are visiting on the environment.

To gauge the impacts of human activities on other organisms, we need baseline data to serve as a point of reference. Acquiring this baseline information requires thorough sampling and generally exceeds the capacity of a state agency or university laboratory. Citizen scientists are essential for these atlas projects.

The Maine Department of Inland Fisheries and Wildlife (MDIFW) has worked with partners on some atlas projects. Perhaps you participated in the Maine Dragonfly and Damselfly Survey, the Maine Butterfly Survey or the on-going Maine Bumblebee Survey.

Maine was one of the first states to produce an atlas of the breeding birds of the state from 1978-1983. The atlas was a bare-bones effort and the publication is mostly a series of maps with records of nesting indicated across the state. Nonetheless, it provides that important baseline to judge future breeding distributions.

MDIFW and four partner organizations began a new Breeding Bird Atlas project last year (click here).  The first year was a great success and we hope the second year will be even more productive.  The project will continue through 2022.

This project has an ambitious scope. The state is divided into over 4000 blocks, each a rectangle of 3 miles by 2.9 miles. Over 900 of these blocks, distributed across the state, are designated as priority blocks to insure thorough coverage of the state. Obviously an army of volunteers is needed to see the project to fruition and the project directors want to involve as many people as possible.

The basic protocol is to visit a site during the breeding season and search for evidence of nesting behavior. Such evidence can be building a nest, feeding young, a nest with eggs, or singing behavior by a male at the same place over a period of more than a week. It is a different kind of birding that most of us do and is tremendously satisfying to really get to know our breeding birds.

Volunteers can participate by either adopting a block or simply making observations anywhere that is convenient for you. If you choose to adopt a block, you are expected to devote 20 hours of observations to that block.

You will report your data either through eBird or by submitting data forms to the coordinators who will enter your data into the database.

Visit the website and download the Volunteer Guide to learn more and perhaps adopt a block. Appendix 1 has a list of the 30 Regional Coordinators. Find the one for your part of the state and contact the coordinator for more information.

Review of Gulls Simplified

By in Field Guides, Identification

No one ever said birding is easy. With 10,000 birds in the world, one inevitably encounters groups of birds that are difficult to distinguish. Hummingbirds in the New World tropics, sandpipers and sparrows are great examples. It’s easy to identify a bird as a hummingbird but which of the 340 species are you seeing?

Gulls are another group of challenging birds. Any school kid can identify a seagull but identifying the species can be perplexing.  Which of the 16 gull species in Maine are we looking at?

The difficulty of gull identification stems in part from the similarity of the different gull species. Although body mass differs among species, every gull has roughly the same silhouette.

In addition, gulls pass through a bewildering series of plumages. Gulls molt all of their body feathers every fall, transforming their appearance dramatically. In the spring, gulls have a partial molt, again altering their appearance. To confound matters further, the timing of the molts differs among individuals so birds that are the same age may look strikingly different.

Finally, gulls may take up to four years to acquire their adult plumage, called the definitive plumage in ornithology-speak. Smaller gulls like Bonaparte’s Gull require only two years to get to their definitive plumage while our larger gulls like Herring Gull and Great Black-backed Gull take four years to reach adulthood.  That’s a lot of plumages to keep track of.

To be sure, there are some birders who delight in the challenges of gull identification. Poring through flocks of hundreds of gulls to find an uncommon gull like a Lesser Black-backed Gull, Black-headed Gull, Little Gull or Sabine’s Gull is a joy to gull enthusiasts.

That level of skill is tough to come by. However, a recent book from Princeton University Press may be a gateway to allow you to acquire those skills. The book is called Gulls Simplified by Pete Dunne and Kevin Karlson. Gulls Simplified: A Comparative Approach to Identification by [Dunne, Pete, Karlson, Kevin]Yes, I am aware that the phrase gulls simplified is a contradiction in terms but the phrase fits this book.

Who knows? Maybe your improved gull identification skills will allow you to be the person who finds a Slaty-billed Gull among the hundreds of gulls at the Hatch Hill Dump in Augusta or some other gull haven!

Dunne and Karlson are both highly skilled birders and popular bird tour leaders. However, neither one has a particular passion for gulls. The authors argue their level of interest is perfect for a book that aims to fill a need for a gull identification guide that is welcoming to any birder.

The distinctive feature of this guide is that identifications are based more on general shape, size, behavior, general color patterns, habitat and comparisons to other known birds in the area. The guide downplays the feather-centered approach that gull nerds use to identify the age and species of a particular gull.

The authors rightly claim that most birders don’t really care whether the Herring Gull they are looking at is one, two or three years old. It is more important to know that it is a Herring Gull. Dunne notes that is easier for him to identify a Lesser Black-billed Gull at 200 feet than at 20 feet because he uses general impressions rather than plumage details.

Dunn and Karlson are pioneers in promoting bird identification by impression, having produced identification guides for hawks and shorebirds that use this technique effectively. The approach works for gulls, too.

The book is packed with excellent color photographs, mostly taken by Karlson. Detailed legends for each photograph describe important characteristics useful in identification. I counted 46 photos for the Herring Gull. There are several photo quizzes, as well, to test your enhanced identification skills.

The guide covers the 20 regularly occurring gull species in North America as well as five rare gulls. A section with photos on hybrids is illuminating.

“Gulls Simplified” is a great addition to the wealth of bird guides we have.

Birding at Rio Lagartos, Yucatán Peninsula

By in Uncategorized

While the United States was plunged into bitter cold by the polar vortex in January, my wife and I were enjoying the sun in Mexico on the Yucatán peninsula, along with four friends from South Carolina. The six of us had gone down to visit a number of old friends that we had not seen since August or September. In our travels, we made a lot of new friends as well. Of course, all of these friends were feathered.

I’ll just describe a portion of our birding adventure to give a flavor of Yucatán birding. Rio Lagartos is a well-known birding hotspot in the Yucatán so we made our way to this small coastal village west of Cancún. We procured the services of Diego Nuñez, the proprietor of Rio Lagartos Birding Adventures in advance (http://www.riolagartosnaturetours.com/birding.html),

Diego owns a restaurant and a small lodge so all our needs were met there.

We arrived late in the afternoon on a Saturday and went to the deck of the restaurant to relax. Diego has 15 hummingbird feeders set up on the deck. The first hummer we saw was indeed an old friend, a Ruby-throated Hummingbird.  Over the course of the next hour we also had great looks at Cinnamon Hummingbirds, Canivet’s Emerald, White-breasted Emeralds and Mexican Sheartails. The sheartails were particularly striking with large orange spots on their tail feathers.

Our backs were to the Rio Lagartos as we watched the hummers. We were surprised to finally turn around to look over the river  and saw about 100 American Flamingos on the far side, settling down into shallow water to spend the night. Spectacular!

We met Diego early the next morning for a five-hour land bird excursion. Diego brought his eagle-eyed daughter, Andrea, along as well.

The first birds at our initial stop were wintering migrants: a pair of Indigo Buntings, a Rose-breasted Grosbeak, Yellow Warblers and Common Yellowthroats.

Diego’s birding van

Several vultures were flying overhead

Our merry band with Diego and Andrea

with their wings held in a shallow V. No, not Turkey Vultures but Lesser Yellow-headed Vultures, a new species for both of us.

The morning continued in this fashion, encountering familiar wintering birds and unfamiliar Mexican residents. This region of the Yucatán is largely scrub vegetation with scattered pockets of trees here and there. Diego knows the area like the back of his hand so stops we made were always productive.

A small pond had more old friends including 20 Blue-winged Teal, 10 Least Sandpipers and two Common Gallinules. A Sora called from the surrounding marsh but remained hidden. However, a larger rail, the Russet-naped Wood-Rail did give us superb views. Several long-toed Northern Jacanas were delightful.

A trip through a small farming community produced a couple of Turquoise-browed Motmots with electric green plumage and racket-shaped tail feathers. We definitely knew we weren’t in Maine. Bronzed Cowbirds and Scrub Euphonias, a type of finch, appear as well. At one point, five species of orioles were present at one site, a riot of yellow and orange.

We had great looks at some of the birds endemic to the Yucatan Peninsula including Yucatán Woodpecker, Yucatán Flycatcher and Yucatán Wren. We had great looks at a Laughing Falcon and a White-tailed Hawk.

Diego saved the best stops for last. As we neared town, we visited a couple of small embayments. At the first, we had views of flamingos and Black-necked Stilts from no more than 50 feet.

American Flamingos

A second stop along a mangrove stand held many roosting birds including White Ibises, Snowy Egrets, Great Egrets, Roseate Spoonbills and a Black-crowned Night Heron.

White Ibises

The highlight was two Boat-billed Herons, similar to the Black-crowned but with a massive bill. A great end to a satisfying morning of birding.

We saw 83 species on our morning trip. We renewed friendships with a number of species and look forward to seeing many of them again in the summer here in Maine.

Highlights of Maine Christmas Bird Counts – 2018/19 – III

By in Christmas Count Summaries

This post is the last of three reporting highlights of some of the Maine Christmas Bird Counts. This counts, conducted on a single day within a permanent circle with a 15 mile diameter, are compiled by the National Audubon Society. We’ll jump all around the state today.

The Waterville Count, held on December 16, was exceptionally good this year with 59 species found. That species total equals the totals from several coastal counts.

Two dams on the Kennebec usually keep some water open. This year the open water yielded 217 Common Goldeneye, six Barrow’s Goldeneye, seven Hooded Mergansers and 32 Common Mergansers.

Predatory birds included 15 Bald Eagles, a Merlin, a Peregrine Falcon and a Northern Shrike.

Both waxwings were present with Bohemians outnumbering Cedars, 341 to 18. A single Snow Bunting was seen, unusual for this species that flocks in the winter.

Irruptive finches were represented by 20 Pine Grosbeaks and our Pine Siskins.

Lingering birds included a Belted Kingfisher, a Northern Flicker, five Eastern Bluebirds, four Savannah Sparrows, two Swamp Sparrows, a Brown-headed Cowbird and a Rusty Blackbird.

We’ll head northwest to Hartland where counters there found 33 species on December 22. With most water frozen, Mallards and American Black Ducks were the only waterbirds.

Highlights included a lingering Northern Flicker, 38 Bohemian Waxwings, a single Purple Finch and a dozen Common Redpolls.

Proceeding southwest, we come to Farmington where 39 species were found on December 27. Not a single waterbird was detected.

The counters did get the trifecta of woodland hawks: one Sharp-shinned Hawk, two Cooper’s Hawk and a single Northern Goshawk. A hawk wannabe, a Northern Shrike, was found as well.

Four lingering Eastern Bluebirds were remarkable for this part of the state. Bohemian Waxwings were present to the tune of 310 individuals. The northern finch list was impressive: 33 Pine Grosbeaks, 15 Common Redpolls and 37 Evening Grosbeaks.

The Misery Township count was held on December 23. About 30 miles of Jackman, this area is the least developed of any Christmas Count circle in Maine. The human population is sparse and most of the area is timberland. The low habitat diversity and the harsh climate is reflected in a modest species count every year. But the quality of the birds is outstanding.

Fourteen species were found this year: seven Ruffed Grouse, three Bald Eagles, two Downy Woodpeckers, two Hairy Woodpeckers, ten Canada Jays (formerly Gray Jays), 20 Blue Jays, one American Crow, 24 Northern Ravens, 123 Black-capped Chickadee and a single Boreal Chickadee, 24 Red-breasted Nuthatches, three White-breasted Nuthatches, two Northern Cardinals and five Pine Grosbeaks.

Note the absence of birds of open countryside like Snow Buntings or sparrows and the lack of birds associated with human developments (gulls, Rock Pigeon, European Starling, House Sparrow).

We’ll continue with a coastal trip to Thomaston-Rockland where a count there on December 15 yielded a list of 68 species.

Fourteen species of waterfowl were present with 14 American Wigeons being the most unusual.

Lingering breeders included five Great Blue Herons, a Belted Kingfisher, a Northern Flicker, an American Kestrel, two Carolina Wrens, eight Eastern Bluebirds, three Northern Mockingbirds and a Savannah Sparrow. An Eastern Phoebe was a nice found during count week but was not seen on count day.

Notable birds seen from shore included five Razorbills and three Bonaparte’s Gulls. A Peregrine Falcon and a Northern Shrike were sighted.

A pair of Snow Buntings were welcome sights in a winter where these winter visitors are not very common this year. Four Pine Grosbeaks were the only northern finches sighted.

Bopping over to Sweden in Oxford County, we discover their count on December 27 produced a list of 31 species. American Black Ducks and Mallards were the only waterfowl found with much of the water frozen over.

Three Red-bellied Woodpeckers were good finds for this part of the state. Northern finches found were three Evening Grosbeaks, one Red Crossbill and one Pine Siskin.

«‹ 12 13 14 15›»