If large totals have seemed lacking this spring, you’re not alone in that observation. The season’s longshore flight has been noticably absent of 20,000 or 30,000 bird mornings. The biggest culprit likely lies with the lack of south winds. After a super warm February, March has been averaging 6 degrees cooler than last March. The graphs below show our local weather station in March 2016, and March of this year. Of note, look at the winds. Last year we had several days of sustained south winds, before a new front would come in. This year, the south winds are almost immediately accompanied with a front and precipitation.
In 2012, we conducted 21 longshore flight counts in the month of March. In 2016, last year, we had 16 counts done. This March has only seen 13 days with longshore flights. Many of those weren’t south winds. Obviously, south winds are the best for measuring migration. Followed by westerly winds, and then finally east winds. North winds are the worst. Wind speed can also affect this. When the weather’s not conducive to migration, anything other than a north wind will be measured, as was the case today, March 29.
With east winds blowing, a typical songbird flight will not happen in any significant quantity, but if the sun is shining, a few migrating thermal riding birds may push off and be forced against the lakeshore, when you’re east of Miller beach. This produced the best Sandhill Crane count since March 5, with 2,376 going by.
With no passerine distractions, raptors put on their best migration of the season at the dunes longshore tower today. 307 raptors went by, with Red-tailed Hawks (154) being the most abundant. The full list of raptors counted was:
91 Turkey Vultures
4 Northern Harrier
42 Sharp-shinned Hawk
1 Cooper’s Hawk
1 Bald Eagle
13 Red-shouldered Hawk
154 Red-tailed Hawk Including 4 dark morphs.
1 American Kestrel
Unfortunately, the next 7 day forecast doesn’t look good still for south winds. NOAA’s 8-14 day outlook shows above average temperatures, and below average precipitation. This may bring the needed south winds to kickstart the dunes bird migration. Until then, we’re enjoying just a small trickle of the dunes potential.
Today’s’ full count is here.