Long clawed…rice eaters?

Long clawed…rice eaters?

Aside from my main project here at the park, I have been leading preliminary research on phenology and behavior of a declining grassland obligate species. Grasslands and their species have experienced declines due to numerous reasons, such as loss to agriculture, overgrazing, and climate change. 

The scientific name of this bird roughly translates to long claw rice devourer, denoting it the old name: rice bird. Bobolink (Dolichonyx oryzivorus), a medium-sized songbird, are a very unique species in several different ways. They are the only known terrestrial bird to migrate through the Galapagos. Charles Darwin actually collected a bobolink in 1835! Another strange aspect of the bobolink is that they have two complete molts annually unlike other birds, who typically have one (some species like marsh wren also have two molts annually).

Four male bobolink perched on a bush
Female bobolink foraging, potential provisioning

Unfortunately due to climate change and agriculture practices, bobolink fall into an ecological trap [this means due to the constantly changing environment and lack of suitable habitats, the bobolink will settle for poor-quality and/or unconventional places to breed]. Bobolink breed in North America and overwinter in South America; their breeding season ranges from March to August. They will often find themselves in hayfields, and their active nesting period coincides with the first haying cycle of the season. They are ground nesters and raise their young in those nests, due to current haying cycles and patterns the bobolink are often killed in the cultivation process.

According to the “State of the Birds 2022” bobolink are a tipping point species, meaning that they have declined by at least 66% in the last 50 years and are expected to lose 50% of the remaining population in the next 50 years. The regional population of Ohio has been declining around 5% annually, in the Cuyahoga Valley area it’s been closer to 3%. Aside from eBird there is little data on the park’s population of bobolink, they are only found in one field in Cuyahoga Valley National Park.

This species could be considered a point of contention due to their phenology and the timeline of farmer’s crop seasons. Collecting and analyzing this information will allow us to make conservation and management strategies to best support grassland species, especially the bobolink who continue to lose habitat. In a broader scheme we hope to contribute data on the local population and developing high quality sites.

My personal goal is to be able to make a plan for the next intern or technician in order to conduct surveys on the bobolink such as arrival & departure dates, breeding signs, provisioning, spot mapping, and mist-net protocol. With regards to mist-netting the end goal is to be able to color band individuals to keep record of return rates and survivorship for long term monitoring.

Decoy bobolink (sock and felt) on a fence with playback
Ray Jalbert taking morphometrics of male bobolink

*All banding, marking, sampling, and handling is conducted under authorized Bird Banding Permit issued by the USGS BBL*

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