Migration Forecast May 12-15 plus 16-17 update: Looking forward to the weekend

Male Bay-breasted Warbler: Good numbers have been seen for the last few days.

Tuesday, May 12: The opening weekend for The Biggest Week in American Birding may not have seen quite the volume expected, however, diversity was ever present in most areas along Lake Erie. Finding close to (or over) twenty species of warbler over the past weekend wasn't too difficult a task as more species like Tennessee, Magnolia, Bay-breasted, Chestnut-sided, American Redstart, and Canada Warbler began to move into the marshes. Along with some of the "regular" migrants, many birders at the Magee Marsh boardwalk were fortunate enough to also observe Mourning Warbler, a Kentucky Warbler, and a few Hooded Warblers -- the latter two being overflight species that have flown too far north during migration.  

Other notable sightings from around the area include a few Summer Tanagers seen at both Magee Marsh and Oak Openings Preserve Metropark, a Chuck-will's-widow heard multiple nights in the campground at Maumee Bay State Park, and a Yellow-headed Blackbird seen during the auto-tour at Ottawa National Wildlife Refuge. And -- continuing the productivity it has had over the past couple of weeks -- Metzger Marsh has been host to upwards of 500 American Golden-Plovers, a few Black-bellied Plovers, two Black-necked Stilts, a Marbled Godwit, a few American White Pelicans, and even a rare-in-spring Hudsonian Godwit.

Bird activity during the upcoming week will mostly be affected by wind direction Tuesday night. With a cold front advancing towards the east, many birds may try to ride ahead with the receding southwest winds and cross Lake Erie. But the volume of remaining migrants on Wednesday and Thursday will mostly be determined by the timing of the shift from southerly winds to northerly winds on Tuesday night, May 12. 

If winds shift late Tuesday night/early Wednesday morning, many birds will be gone on Wednesday and Thursday -- as songbirds travel at night, riding a tailwind from the south. But if winds shift early enough Tuesday night as forecast, many birds that have recently arrived should stick around for the next couple of days while winds continue from the north. On days with northerly winds most birds will move away from the shoreline, so these will be good days to explore areas a mile or so away from the lake such as Pearson Metropark, the trail behind BSBO, and the woods behind/north of the visitor's center at Ottawa NWR. 

This temperature and wind shift will be caused by a high pressure system that is expected to cover much of the eastern U.S. until Thursday night. But by Friday, when a new low pressure system is expected to move and winds shift back to the south, we could see the departure of any birds that were held up during the week and potentially the arrival of a few new birds. The good news with this high pressure system holding over the area throughout Wednesday and Thursday is that many migrating birds still heading north could become trapped in the southern U.S. waiting for the winds to change. So, by Saturday and Sunday (but most likely Saturday assuming favorable conditions) the second pulse of the second wave of migrants -- which is dominated by male Magnolia Warblers and usually has the largest volume of birds -- could bring a high number of birds into the area. If this back up does occur, there is also the potential that signs of the third wave may be present as well, bringing more flycatchers into the area. 

With the way the weather has been changing, it may be too early at this point to say that Saturday will be a big day. Further monitoring of the weather and radar over the next few days should reveal a clearer picture by the weekend and an update will be posted with any changes and new predictions. But for the moment, expect a moderately slow week picking up by Friday May 15, hopefully leading up to a big weekend.   

Update: Per tonight's forecast, conditions still look good for a high volume of birds -- as expected at this point during migration -- to move into the area this weekend. Late tonight (Friday the 15th) winds will begin to shift to the southwest, bringing high temperatures again and also some rain. Depending on the time and place this rain hits, many birds could be forced to land along the shoreline or be dispersed throughout the surrounding area -- only Saturday and Sunday morning observations will confirm where the majority of birds are being seen.

Be prepared to cover any equipment as scattered thunderstorms and a chance for rain are predicted throughout the day for both Saturday and Sunday, May 16 and 17. Check the weather periodically while out, as birding should be excellent when a break in the rain does occur.