Part 2 Migration>> April>> May>> June>>
This installment of the year long series covers the months April through June. This period is one of great change in the birds present in Connecticut. A flood of migrants return to their northern breeding grounds. Some of these species will be Connecticut breeders while others will pass through on their way to more northerly territories. The returning breeders are full of song and a working knowledge of bird songs and calls is immensely helpful. At the end of this article we will discuss what audio resources are commercially available to birders to learn the vocalizations of the species present in our state. There is nothing quite so beautiful as the chorus of bird songs during the first blush of a morning in May. Being able to identify which species are singing without actually seeing the birds is icing on the cake.
It is highly recommended that you use one of the recently published site guides on birding in Connecticut in tandem with the strategies laid out in this series.
In order to bird these months effectively you must have a basic understanding of spring migration and its manifestation in Connecticut. Before we discuss the months of April, May, and June, we will discuss the spring migration phenomena.
Understanding Migration: The Key to Spring Birding
It isn’t necessary to be an authority on migration, knowing just a little will help immensely. Volumes have been written about migration but we will cover just the basics you need to know to put more birds in your birding.
Spring migration is driven by the instinct to reproduce. Usually the male of a species migrates first to set up territories to attract a mate. The females will follow after. The instinct to migrate is very strong and pushes individuals to take great risks to reach the breeding grounds. This is somewhat different from fall migration in that birds will move north even in adverse weather. In fall birds tend to wait for favorable weather to move south. Still, the largest spring movement of birds occurs with favorable weather. Nearly all the Spring migration occurs form the second week in April through the first week in June. The heaviest migration into and through Connecticut occurs between the last week in April and the third week in May. Large numbers of birds, or "waves", can suddenly occur in Connecticut if inclement weather blocks migratory movement for a couple of days or longer. This inclement weather is referred to as "blocking weather" because while it occurs it blocks much of the migration. The birds tend to "pile up" behind the foul weather and wait for clear skies. When blocking weather moves away it is usually followed by clear nights and a southwest wind. When this occurs a heavy movement of birds is likely. Birding these beautiful mornings can be very productive. It is a very good idea to be an amateur meteorologist and to watch what weather is occurring to our south, where the birds are coming from. Watch for these migration dams and be ready to hit the field when they break. During this period, clear nights with southwest winds means birds, plain and simple.
Most songbird species, but not all, migrate at night. They arrive in the early hours and begin to disperse and forage at first light. In spring many of these birds will be in song, helping the birder find them. This is where a working knowledge of birdsong can be an immeasurable help. The early migrants favor habitats of low elevation sheltered areas such as wetlands. These low lying areas are warmer and tend to be where the first insect blooms occur. These insect blooms will be an important food source for the return migrants. Locations such as river valleys, wooded swamps, coastal marshes, pond and lake edges are where you are most likely to find the first returning songbirds. As the migration continues the birds will move further into our state and will be found at higher elevations. To envision where the migrants are likely to be most concentrated in the state during the migration, imagine the progression of an immense flood covering Connecticut. At the start, the low coastal areas would be covered. As time progressed the water would work up river valleys and fill wetlands. During the middle of the flood the intermediate elevations and low hills would be covered. Lastly, the highest elevations would be flooded. This flooding model is a rough approximation of how the migrant birds return to our state.
Different species have different peak times for migration in Connecticut. Yellow-rumped Warbler is an early migrant easily found in the third week of April while Yellow-bellied Flycatcher is a late migrant found passing through as late as the first week in June. Knowing when a species should be present will increase your chances of finding it. Migrants are often found in habitat that reflects their breeding habitat. When searching for particular species this should be borne in mind. As a rule, the further north a species breeds, the later it migrates. Therefore more southerly breeders such as Blue Grosbeak arrive on their breeding grounds before northern breeders like Mourning Warbler.
The number of species and the number of individuals that pass through Connecticut during this period is very impressive. This article can not cover the detail and complexity of this phenomena but will cover generalities in attempting to improve your birding strategies during this wildest period of the birding year.
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April usually arrives just as March went out, full of promise but often dreary and wet. The wintering birds are now heading north and this is a good time to see some of these species in their breeding plumage. Common Loons, Horned Grebes, Snow Buntings, Lapland Longspurs, and many other species will be in various stages of molt. Some may be virtually complete. As these birds head north , the first real push of migrants from the tropics and beyond fly into southern New England. From a birder’s perspective, winter finally departs and spring arrives during the month of April.
April: General Strategy
During April we transition from winter birds to summer birds. The departing birds of winter often hold a surprise or two as birds move through our area so pay attention to waterfowl areas early in April. The first arriving birds of summer occur coastally and at the low, wet, warm areas we have discussed. Therefore the most productive birding will occur in these areas. Try to visit coastal areas if you can but wherever you bird, look for low sheltered wetlands. These warm pockets are going to be where you find the spring arrivals first. Think low elevation, think sheltered warmth, think wetland, find birds! By the end of the month things will be getting very busy indeed.
If there are wintering species you still haven’t seen, the first week in April is likely to be your last chance until the end of the year. Waterfowl will be in full migration now and large numbers of loons, grebes, geese, and ducks will be passing through. Wood duck and Blue-winged Teal are now to be found and often Snow geese will be seen passing high overhead. Listen for their distinct honking, this will alert you to look for the very high white "vee" formations. While many Snow Geese may pass over on migration they seldom land in any numbers in Connecticut. Remember, birding is three dimensional, always keep an eye on the sky!
A visit or two to the coastal marshes and beaches during the first week of April will likely be productive with the return of early shorebirds such as Piping Plover, Yellowlegs, Ruddy Turnstones, and a few others. The marshes will now have Ospreys displaying above them and early herons and egrets hunting in them. Little Blue Herons and Yellow-crowned Night-Herons, both rather uncommon in Connecticut, are sometimes found now among Great Egrets and Snowy Egrets. Coastal marshes are excellent locales to find the first swallows to come back. Tree Swallows and Barn Swallows are usually the first to arrive with Cliff Swallows being the last.
During the second week of April the real song bird migration starts to arrive. We are now entering a four or five week period during which birders want to be everywhere at once. As the British say, it’s all go now! With so much to look for and so little time to look, it is imperative to be smart in your choices of places to go. Some of the first species that will turn up are swallows, Eastern Phoebe, Hermit Thrush, both Kinglets, Yellow-rumped Warbler, Yellow Warbler, Louisiana and Northern Waterthrushes, Palm Warblers, and others. As the third and fourth weeks of April roll in the number of returning bird species grows rapidly. Repeated visits to an area will turn up different bird mixes daily. Find an area that is attracting birds and visit it often. Raptors are also returning now and you should watch the sky for such species as Red-shouldered Hawk and Broad-winged Hawk.
Inclement or gray weather in the last two weeks of April are good for checking coastal marshes for birds such as herons, egrets, migrant falcons, shorebirds, and rails. While a good number of these may be around all summer, the marsh vegetation will be short and brown now, allowing for much easier spotting and viewing of birds. Be alert for anything and keep those ears open!
Where, When, and Weather
We have already discussed weather. Remember to watch for migration weather, southwest winds will carry migrants into Connecticut. Northerly or easterly winds at this time is not good news for birding.
The best birding of the day will usually be early, very early. If you want to see the most birds you need to be out at first light. Many species migrate at night and will be roving and feeding during the early hours. These birds will be less active and quieter later in the day. It is a given that the most serious birders will be sleep deprived during April and May!
Coastal marshes that are very productive include Sherwood Island State Park in Westport, Great Meadows in Stratford, Milford Point in Milford, Hammonasset Beach State Park in Madison, Great Island Marsh at the mouth of the Connecticut River, Rocky Neck State Park in Niantic, and Barn Island Wildlife Management Area in Stonington.
For returning land birds numerous low lying areas and wetlands exist. Try to find areas near you and visit these repeatedly throughout the migration. State Parks and Forests often offer good birding possibilities. You may have heard the term "migrant trap" used. A migrant trap is a location that tends to concentrate migrating birds. A spring migrant trap is usually an area of natural habitat surrounded by an urban area, such as a city park. In Connecticut there is one famous and very productive spring migrant trap, East Rock Park in New Haven. This park is dominated by a massive forested rock formation with a trail system in the middle of a city that acts as a magnet to spring migrants. East Rock Park has seen some very impressive concentrations of spring migrants over the years. Coastal peninsulas can also cause concentrations of migrants.
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There are more species of bird present in Connecticut during May than during any other month of the year. This fact makes it a very busy month for birders. All the breeding species are on territory and a number of through migrants are present. The first two weeks of the month are the peak of the birding year. It is a time when you need to be everywhere at once. Species that breed in Connecticut do not necessarily do so evenly throughout the entire state. In order to find most of them you have to visit different parts of the state. It is nearly impossible to do justice to birding the month of May in an article of this nature.
May: General Strategy
There are two general groups of migrants we need to discuss. One is the returning Connecticut breeders, and the other is through migrants, species that are heading further north to breed. The first two weeks of May should be utilized to look for the species that are migrating through. Species that breed to our north will be easier to find now when they are singing, such as Cape May Warbler. If you know of a migrant trap such as East Rock Park it pays handsome rewards to visit it repeatedly during these two weeks. Migrants can be everywhere now, even in a lone tree in your backyard or in the parking lot at work. Explore all habitats you can to find different species. During the second half of May you can turn your attention to breeding species. This will require visiting different geographic areas in Connecticut. The best strategy for the month of May is bird often, bird hard, bird everywhere! Well, do the best you can.
May, (the first half): Discussion
Good weather during the first half of May should be dedicated to searching for migrant land birds such as Flycatchers, Thrushes, Vireos, Warblers, and Sparrows. Inclement weather or days with easterly winds should be used to search coastal areas for migrant waterfowl, herons and egrets, shorebirds, gulls, and terns. If your birding time is limited during May, you should concentrate on songbird migration at the expense of shorebirds and other coastal species. You will get a chance for many of these again during the fall migration.
When searching for songbirds you should either visit migrant traps where you will find a nice mixture of species, or visit different habitat types to find the greatest number of species. Forests will produce species such as Ruffed Grouse, Wild Turkey, Black-billed and Yellow-billed Cuckoos, Least Flycatcher, Great Crested Flycatcher, Blue-Gray Gnatcatcher, Thrushes, Vireos, a mixture of warblers including Northern Parula, Magnolia, Black-throated Blue, Blackburnian, Cerulean, Black-and-white, American Redstart, Ovenbird, Scarlet Tanager, Rose-breasted Grosbeak, and Baltimore Oriole. Forest edges and brushy areas such as powerline cuts will produce species such as Ruby-throated Hummingbird, Eastern Kingbird, Brown Thrasher, White-eyed Vireo, Philadelphia Vireo (rare in spring), Golden-winged Warbler (rare), Prairie Warbler, Palm Warbler, Indigo Bunting, Eastern Towhee, Field Sparrow, and White-crowned Sparrow. Wet woodlands can produced a species mixture that may include Acadian Flycatcher, Winter Wren , both Waterthrushes, Hooded Warbler, Wilson’s Warbler, Canada Warbler, and Lincoln’s Sparrow. Coniferous tracts, especially ones with some spruces, can have Swainson’s Thrush, Cape May Warbler, Black-throated Green Warbler, Pine Warbler, Bay-breasted Warbler, and Blackpoll Warbler. Riparian areas may have Solitary or Spotted Sandpipers, Belted Kingfisher, Bank Swallow, and Cerulean Warbler. Fresh water marshes and swamps could produce Least Bittern, Green Heron, Rails, Common Snipe, Willow and Alder Flycatchers, swallows, Marsh Wren, Yellow Warbler, and Swamp Sparrow. Open grassy areas with a few trees may have Vesper Sparrow, Grasshopper Sparrow (local), Bobolink, Eastern Meadowlark, and Orchard Oriole. Coastal marshes should produce a wide variety of species including herons and egrets, Ibis, Rails, Shorebirds, Terns, Willow Flycatcher, Swallows, Salt-marsh Sharp-tailed Sparrow, and Seaside Sparrow.
Prioritize your birding locations. If you happen to be retired or independently wealthy you can go everywhere. This luxury is not the norm among birders unfortunately. During the first two weeks of May the priority should be, from most important to least; migrant traps such as East Rock Park, wooded swamps and fresh water marshes, river bottoms, woodlands with brushy edges, coastal marshes, grassland habitat.
May, (the second half): Discussion
The more northerly breeders are now passing through, as well as the females of earlier species. Additionally, many birds are now on territory in Connecticut. Migrant traps are still worth checking but you may not want to make them your first priority. To find the later migrants it often is better to search particular habitats. It is still a good idea to make an effort to find through migrants but now you can start a more serious search for uncommon or local breeders. Some late migrants and their favored habitats include Olive-sided Flycatcher in wet or open areas with dead trees, Eastern Wood-Pewee in any woodland, Yellow-bellied Flycatcher in deep forest often at a higher elevation, Gray-cheeked/Bicknell’s Thrushes in deep forest, and Mourning Warbler in dense and damp woodland. By this time the more northern sections of Connecticut are starting to get quite "birdy". Some breeding species have limited ranges in Connecticut and are mostly found in the higher elevations. These include Yellow-bellied Sapsucker, Alder Flycatcher, Common Raven, Black-throated Blue Warbler, Yellow-rumped Warbler, and Dark-eyed Junco.
By the last week in May you should be heavily targeting uncommon and local breeders. These include the following; Least Bittern, Northern Bobwhite (may be extirpated as a sustained breeder), Upland Sandpiper, Sora, Common Raven, Golden-winged Warbler, Grasshopper Sparrow, and Orchard Oriole. Word of mouth is often the best way to find where these species can be found in Connecticut but a site guide such as the Connecticut Birding Guide (Devine & Smith) can be a big help. As of this writing both Upland Sandpiper and Grasshopper Sparrow breed on parts of Bradley International Airport in Windsor Locks. While you are searching these out you will undoubtedly turn up other new species for the year as well.
A number of species are best found at night. This is a good time to look for them by spending a few hours listening in the dark. Judicious use of taped vocalizations of these species can help a great deal to find and see them but PLEASE do not use tapes liberally. Heavy use of bird tapes is widely considered detrimental to the breeding birds and birders nearly always play them more loudly than necessary. The birds only have to hear the tape, not be blown off the nest. These night birds include Virginia Rail, Clapper Rail, King Rail, Black Rail (very rare), Soras, several species of Owl, Common Nighthawk (mostly migrant), and Whippoorwill. Some of these species are very local breeders, like King Rail, and in the case of Whippoorwill need large tracts of unbroken woodland. Many nocturnal species, and some diurnal species, will vocalize to tapes of Owls such as Eastern Screech Owl. It is always a good idea to try this first.
As time permits you may spend some time shorebirding. You are unlikely to see anything that you won’t see on fall migration but you will see some of these species in their breeding plumage now.
Where, When, and Weather
Find out where a migrant trap exists near you and visit it. If you know of no such place, try coastal parks and forest, especially on coastal peninsulas. Some such places are Greenwich Point Park in Greenwich, Sherwood Island State Park in Westport, East Rock Park in New Haven, Hammonasset State Park in Madison, Nehantic State Forest in Old Lyme, Bluff Point State Coastal Reserve in Groton, and Barn Island Wildlife Management Area in Stonington. As the month wears on visit forest and wetlands in the interior. River Road in Kent is one of the best known Spring birding locations in Connecticut. This location is always productive in the second half of May and has the largest concentration of Cerulean Warblers in our state. This is also an excellent locale to find Black Vulture, a very local species in Connecticut.
When? During May, when you are awake you should be birding, and try not to sleep anymore than you have too!
The previous discussion on weather still holds true. When the weather is good for migration then bird for songbirds. When the weather is inclement or otherwise not conducive to songbird migration, spend time birding for coastal birds such as Terns and Shorebirds.
April and May Advanced Birding Tips
Prolonged blocking weather in April is sometimes followed by clear weather with a very strong southwest wind. When this occurs there is often a number of southerly species that overshoot their normal ranges and end up in the northeast. Summer Tanager and Blue Grosbeak are notorious for this. The possibility of even better rarities exists however. When these conditions occur you should be alert for such species as Swallow-tailed and Mississippi Kites, Chuck-wills-widow, Yellow-throated Warbler, and even Swainson’s Warbler. You should also be alert for southern shorebirds during the April/May period, American Avocet, Wilson’s Plover, and Snowy Plover are real possibilities. When a southwest wind howls in late April, start looking for rarities from the south.
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During June a few species are still migrating north through Connecticut, such as Olive-sided Flycatcher. For the most part however it is time for the birds to breed and raise young. This month is the time to find all the uncommon breeders you haven’t yet seen this year. It is also a good month for rarities.
June: General Strategy
Target the breeders you still need. It is the lucky birder indeed who "gets" everything on migration. It often takes searching for breeders to fill the year list out. It is well worth the effort to visit forests, fields, and beaches during the month. If there are summer bird counts or breeding surveys in your area get involved. Rare and uncommon species are often found on these counts, and you will be making an important contribution. Try to bird areas where you haven’t been yet this Spring.
Breeding is now occurring at a fast and furious pace. Many of the long-distance migrants only spend a brief time here. Once the eggs have hatched it time to feed hungry mouths. The chore of feeding the new members of the species is not an easy one, it requires much effort. The hard working parents of some species are sometimes much easier to find now then at any other time. This is particularly true of raptors and Owls. It is not unusual to see frazzled Great Horned Owls hunting in daylight to feed their fast growing offspring. For the birder, the hectic frenzy of May has finally subsided and June allows for a more relaxed style of birding. By the end of the month the focus of birding will be switching back to shorebirds and the coast. The amount of time we spend looking at the feathered gems we call Warblers is amazingly, and regrettably, brief. Take the time to appreciate these lovely creatures while the visit us.
It’s the end of June and the southward migration has already begun. Female Wilson’s Phalaropes have left the young in the care of the males and are headed for winter quarters. It is possible to have a Wilson’s Phalarope migrating south past a north-bound Olive-sided Flycatcher. It’s a wild world isn’t it?
June: Advanced Birding Tip
The month of June is known as one of the best months for rarities to show up. It is prime time for species such as Mississippi Kite, Fork-tailed Flycatcher, and Scissor-tailed Flycatcher. Even Bridled Tern is a possibility. When a bird fails to find a mate or loses a battle for territory, it sometimes starts wandering. These wandering individuals sometimes show up out of the species normal range. Additionally some rarities are found during bird counts and breeding bird surveys. The point is, just because spring migration has pretty much ended, you shouldn’t take the month off form birding. Try visiting areas you haven’t birded yet this spring. Who knows when you are going to stumble onto that Henslow’s Sparrow singing in the wet field down the street? You know, the one you drive past every day without stopping.
Recommended Bird Recordings for the Birder
You can do nothing more effective to improve your Spring birding success than improving your birding by ear. The single most important commercially offered product is the Peterson’s Field Guide to Bird Songs-Eastern/Central North America. This set of cassettes or compact disks covers nearly all the songbirds to be found in Connecticut and it is the cornerstone of an audio reference library for our area. Another worthwhile product is Guide to Bird Sounds from the Cornell Laboratory of Ornithology keyed to the National Geographic Field Guide to the Birds of North America. This does not cover the full spectrum of Connecticut species however. Cornell’s Songs of the Warblers of North America is excellent for the birder who wants to expand his knowledge of this group of impressive migrants. Quite useful to beginner/intermediate birders is the Birding by Ear series. These tapes use a comparison methodology presenting similar songs to the listener to teach the differences. A number of other recordings are available that specialize in specific bird groups but these are only helpful if you have already mastered the basics.
By the end of June your year list of species seen in Connecticut should be around 200 species or more. Experienced Connecticut birders routinely exceed 250 by the end of June, but this requires a serious time commitment. Whatever your total is for the year at this point, it is time to radically change the birding pace. The need to be everywhere at once and the possibility of finding new birds almost anywhere is over. Now comes the challenge of the fall shorebird migration, perhaps the biggest challenge of the birding year. Finding and identifying as many species as possible really requires a very well thought out plan. The next installment of this series will address that challenge in detail.