The Long-distance Flyer
by Juanita Baker, Ph.D.
Bobolinks belong to the Icteridae family (New World blackbirds), which includes species of grackles, meadowlarks, cowbirds, orioles, and Red-winged Blackbirds. Birds of the same family have similar characteristics. Icterids often have a melodious, bubbly song and sexual dimorphism – the genders exhibit different characteristics, with males usually being more brilliantly colored and often larger. Gaping ability (the skulls allow their bills to open a gap forcibly) is another Icterid characteristic. Bobolinks have conical bills, allowing them to readily crush grains, as illustrated in Dr. Henry Young’s excellent action photo of this Bobolink relishing his food while grasping the grain stalk on which he is feeding. Yet the bird shows characteristic watchfulness, needing to be always alert to his surroundings.
Characteristic of icterids, male Bobolinks sing a long, bubbly song while sitting on a stalk or during their undulating flight across the fields. Bobolinks are one of the few species that completely molt twice in a year, males becoming drab browns and indistinguishable from females. In addition, their coloring and appearance changes as the tips of feathers wear off. Bobolinks have the longest migratory flight (~12,000 miles round-trip) of any New World passerine—perhaps the reason for the need for new feathers twice a year! National Audubon has a new tool – The Explorer: https://explorer.audubon.org/ – showing the active visual map of the migration of many birds.
The Bobolink map shows migration starting in January with concentrations in three South American countries: northern Argentina, Paraguay, and Bolivia, where Bobolinks (known as the ‘rice’ bird) move in flocks and feed on ripe grains in grasslands. After molting in April, flocks leave by flying north, feeding in Venezuela fields to store up for their arduous flight across the Gulf of Mexico. They land in Florida to refuel for the next flight to breed in the Northern US states and from British Columbia to Nova Scotia, Canada.
Any bird species not seen in Florida during June and July is not likely breeding in Florida. Even though some birds (like herons) breed in other months here, they are also here in June and July. Exploring Regions for Indian River County on ebird.org shows in the illustrated checklist that Bobolinks have only been seen here between the second week of April through the last week in May (when they are flying north to their breeding grounds), peaking during the middle three weeks. They return in the fall migration from the last week in August through the first week in October on their way to South America escaping our winter…so you have another week to get out to fields where they may be seen!