Spring Migration Predictions – First Half of April

Finally, it’s April. March was nice, but very few spring migrants returned to PA compared to what’s in store for us birders during April and May. During April, migration really picks up, and we should see most spring migrants back in the state by the end of this month. I went through the eBird bar charts for the PA and attempted to make some predictions on what species should start to show up, start to leave, and begin to reach peak numbers during the first half of April. My goal with this is to help PA birders be better prepared for the 2012 spring migration and know what to be on the look-out for while in the field, birding. Remember that these predictions are based entirely on eBird bar charts for the state of PA, which you can help to make better and more accurate by using eBird yourself.

Blue-winged Teal – male (Photo by Alex Lamoreaux)


March is the big month for most waterfowl species in PA, when multiple species of geese as well as most of the ducks pass through our state on their way to breeding grounds farther north. April is past the peak for most species, but there are still loads of waterfowl moving through the state during these first two weeks of the month. It is still certainly worth your time to check bodies of water during storms for waterfowl that get pushed down. The only migrant waterfowl species that does peak in numbers this month is Blue-winged Teal, which should peak during the second week. Wood Ducks are also getting close to peak numbers around the state. This past week, I have seen many groups of male Wood Ducks trying to impress females. I have also seen a few pairs of Wood Ducks checking out nest boxes.

Other Waterbirds

Both Common and Red-throated Loon will increase in numbers throughout the state during the first half of April. Pied-billed Grebe is at peak levels throughout the state now. Red-necked Grebes, which are uncommon to rare migrants in the state are also most-often seen during the first half of April. Double-crested Cormorants should return to most areas of the state during the first half of the month, if they haven’t already. American White Pelican and Brown Pelican are both very, very rare in the state but the first two weeks of April having been good for them in past years. Large bodies of water are the most likely locations for finding the two pelican species, but they could also be seen in flight as they soar northward – so keep an eye out! As with the waterfowl, other migrant waterbirds are often forced down to bodies of water during storms.

Double-crested Cormorants are returning to PA now (Photo by Alex Lamoreaux)

Herons and Rails

American Bittern – I have had the best luck finding this secretive species during spring migration in PA (Photo by Alex Lamoreaux)

The first half of April is when a lot of our herons and egrets begin returning to the state. Both Great Blue Heron and Great Egret are on the increase now, watch the sky for groups of these large herons migrating overhead as well as any marsh body of water. Black-crowned Night-Herons and American Bitterns will also begin to pass through the state – look for these secretive species in sheltered wetlands and marshy areas. This time of the year also has great potential for vagrant heron and egret species such as Snowy Egret, Little Blue Heron, Tricolored Heron, and Cattle Egret. Both Virginia Rail and Sora are now possible throughout the state and any flooded grass or areas with cattails should be checked for these species.


Most of the winter raptors such as Rough-legged Hawk and Short-eared Owl have already retreated north, but good habitat in the northern part of the state may still hold a few of these species for a few more weeks. Red-tailed Hawk and American Kestrel numbers will begin to decrease as well, as the wintering birds move north and we are left with only the resident birds which will breed throughout the state. Many resident Red-tailed Hawks are already on eggs now and American Kestrels are beginning to pair up and look for nest cavities. There is a pair of kestrels here on the PSU campus that have been guarding a nestbox for about a week now – I can’t wait to see if they successfully raise young!

American Kestrels, like this banded female, are beginning to stake out breeding territories in the state as others move northward. (Photo by Alex Lamoreaux)

Mississippi Kites are possible vagrants this month. Your best chance at seeing one is to put in the hours at a spring hawkwatch. (Photo by Alex Lamoreaux)

April is the big month for migrating Osprey and Broad-winged Hawks. By the second week of this month, both of those species will be back in force. Mississippi Kite is a very rare but certainly possible migrant raptor through the state this month – keep an eye on the sky while you are out birding, or spend some time at your local spring hawkwatch.


Game Birds

During the first half of April, both Ruffed Grouse and Wild Turkey are found in good numbers because they are more vocal and more conspicuous. Listen for the drumming of grouse when you are out birding and look for large groups of turkeys along the edge of forests.


April is the beginning of shorebird migration here in PA. Check the edges of bodies of water, as well as flooded fields and wetlands for shorebirds. Spotted Sandpiper, Solitary Sandpiper, Greater and Lesser Yellowlegs, Pectoral Sandpiper, and Dunlin are the most likely species to be found during the first half of April, but really anything could show up. My friends and I found Centre County’s FOY Spotted Sandpiper on 4/3/12.

Gulls and Terns

Most of the winter gulls have already moved north, but some hotspots in eastern PA like Falls Township Park may still hold a few species like Glaucous Gull and Iceland Gull for a while longer. Right now there are a decent number of Laughing Gulls at Falls Township Park, a species which should increase in numbers as the month progresses although almost all reports are from extreme eastern PA. Bonaparte’s Gulls are approaching peak numbers during the next two weeks. Forster’s Tern and Common Tern are on the increase throughout the state, peaking later in the month. Caspian Tern should be reaching peak numbers during the first half of this month. Bonaparte’s Gull and the three terns I mentioned are most often seen along major rivers and large lakes.


Northern Flicker is currently at peak numbers throughout the state. Yellow-bellied Sapsucker should peak during the second week of April, but from the reports I have seen from around the state, it looks like this species may peak a little early this year – we will see.

Northern Flicker (Photo by Alex Lamoreaux)


Ruby-throated Hummingbirds are slowly pushing through the Carolinas and there are a handful of reports from Virginia. If you can, try to get your feeders filled and outside – any day now a hummer could arrive in PA!

Swallows and Swifts

Tree Swallows came back in big numbers during the last week of March, and are still pushing through in good numbers – most areas of the state should definitely have them by now in proper habitat. Northern Rough-winged Swallow and Barn Swallow have been reported in quite a few locations around the state and will only become more and more common every day. So far this year, two Cliff Swallows have been reported in PA – Drew found on at Bald Eagle SP on 3/31/12 and Rudy Keller found one on 4/3/12 at Lake Ontelaunee. This species should begin to increase in numbers throughout the state soon, the best bet for finding an early one is to carefully scan through large Tree Swallow flocks. Purple Martins have been reported in southeastern PA, near Lake Erie, and at a few other sites around the state. They will increase in numbers throughout the month – scan for them in large swallow flocks and check known nesting spots. Chimney Swifts (not really related to swallows, but I lumped it into this group for simplicity) are quickly moving northward, with many reports in MD and VI. So far, none have been reported in PA but I bet this week someone will find one – probably someone doing a spring hawkwatch.

Tree Swallow (Photo by Alex Lamoreaux)


I am sure most people have already seen their FOY Eastern Phoebe, and I hope they enjoyed it cause there aren’t anymore flycatchers to come for a few more weeks……

Yellow-throated Warblers are most often seen in sycamore trees along waterways, in PA (Photo by Alex Lamoreaux)

Warblers and Vireos

Warblers and vireos; the birds that make spring birding amazing in PA. The real show doesn’t start till May, but be on the lookout for early arrivals over the next few weeks. Louisiana Waterthrush, Pine Warbler, Yellow-rumped Warbler, Yellow-throated Warbler are the most likely, but be on the lookout for early Yellow Warblers and Black-and-White Warblers. Palm Warbler reaches peak numbers this month, so they should be pushing through in decent numbers very soon. Blue-headed Vireo is really the only likely vireo during the first two weeks of April, but be on the lookout – anything could happen.


Chipping Sparrow is on the increase throughout the state right now – listen for their trilling call whenever you are in urban areas. The winter sparrows like Dark-eyed Junco and American Tree Sparrow are declining in numbers rapidly right now as they migrant back north to their breeding grounds. Right now is also your last good chance at seeing a Fox Sparrow till next fall!

Chipping Sparrow (Photo by Alex Lamoreaux)


Both Purple Finch and Pine Siskin are at peak numbers right now at the state level. Keep a close eye on your bird feeders and check American Goldfinch flocks for a migrant siskin hidden in with them! Pine Siskins retreat north to breed but Purple Finches can be found year-round in western and northeastern PA. I was just up at Black Moshannon SP a few days ago and was able to get great looks at Purple Finches, as they sang and chased females.

Purple Finch – male at Black Moshannon SP (Photo by Alex Lamoreaux)

Other Passerines

Brown Thrasher and Gray Catbirds are on the increase throughout the state – on the morning of 4/4/12, we captured and banded Centre County’s FOY catbird while we listened to a Brown Thrasher singing nearby. Brown Creeper and Golden-crowned Kinglet were just at peak numbers during the last week of March, but there are still quite a few around as well as a few Ruby-crowned Kinglets, which will increase over the next two weeks. Blue-gray Gnatcatchers first begin appearing on the coast as they make their way northward, but then will spread to inland areas. There have been a few reports in extreme southeastern PA, but they could start showing up anywhere! House Wrens are also increasing in numbers and should begin to invade PA over the next two weeks. Eastern Bluebirds are beginning to nest around the state. I currently have 2 nests with full clutches of eggs being incubated and another 4 nests being built along my bluebird route, here in Centre County. If you haven’t gone around to clean out your nestboxes, get a move on it! Also keep an eye out for vagrant passerines during the spring migration. Right now vagrant orioles could show up anywhere – bird feeders with oranges are usually the most likely places to find one.


Birds are on the move! Get out and do some birding! If you want, leave me a comment letting me know if my predictions are holding true for your area of the state. Also, if you haven’t started using eBird, right now is the perfect time to start – help make your bird sightings count and become part of a massive citizen-scientist effort to monitor and conserve birds and their habitats. Good luck and be safe out there! Check back in for more predictions during the third week of April.

Virginia Rail – one of three (or more) that are currently at Julian Wetlands, Centre County. (Photo by Alex Lamoreaux)