Col­lege stud­ies spar­rows at Chino Farms

Record Observer - - School -

CH­ESTER­TOWN — In gen­eral, An­drea Free­man’s view of the nat­u­ral world is through a mi­cro­scope. A se­nior bi­ol­ogy ma­jor with an em­pha­sis in cel­lu­lar, molec­u­lar, and in­fec­tious dis­eases, and a mi­nor in chem­istry, Free­man ad­mits she doesn’t get out­side much, which made her sum­mer in­tern­ship with Jen­nie Carr, as­sis­tant pro­fes­sor of Bi­ol­ogy, that much more of an eye-opener.

As a Toll Fel­low in the Col­lege’s Sum­mer Re­search Pro­gram, Free­man worked for 10 weeks with Carr in the re­stored na­tive grass­lands at the Ch­ester River Field Re­search Sta­tion at Chino Farms, help­ing Carr with her on­go­ing study of field spar­rows — con­sid­ered a “com­mon” bird but one which has seen steep pop­u­la­tion de­clines in the last 40 years.

“It def­i­nitely was a dif­fer­ent fo­cus for me be­cause I usu­ally take classes with mi­cro­scopes and stuff like that, and this was out in the field, out­side,” said Free­man. “It took a lot to get used to just from my ex­pe­ri­ences in the class­room. I loved it.”

Carr has been study­ing field spar­rows and hum­ming­birds at the CRFRS since 2014. She has fo­cused the work at the field sta­tion at Chino Farms in part be­cause of the unique habi­tat—the re­stored na­tive grass­lands—that draws the spar­rows. The sta­tion is also home to Fore­man’s Branch Bird Ob­ser­va­tory, whose long-term data col­lec­tion and iden­ti­fi­ca­tion of birds sup­ports her study.

“Be­cause the staff at Fore­man’s Branch has been band­ing birds for so long out there, we have a re­ally well-char­ac­ter­ized pop­u­la­tion of field spar­rows where we know ex­actly how old they are. Very few other stud­ies can do that; they know if they’re two years old, and that’s it,” Carr said. “But we know we have some birds that are seven, eight, nine, and so on. We put color bands on them so we can iden­tify unique in­di­vid­u­als with scopes and binoc­u­lars … when you’re in­ter­ested in age, and you need this lon­gi­tu­di­nal study, you need to know how they did when they were four ver­sus five, five ver­sus six.”

Con­sid­ered com­mon, field spar­rows nev­er­the­less have seen a pop­u­la­tion de­cline of 65 per­cent from 1966 to 2010, ac­cord­ing to the North Amer­i­can Breed­ing Bird Sur­vey. Over the past four sum­mers, Carr has been study­ing whether the age of the bird has a bear­ing on nest­ing suc­cess — in short, do older birds do a bet­ter job of feed­ing their young. Carr has been work­ing with Maren Gim­pel and Dan Small, field ecol­o­gist and Nat­u­ral Lands Project co­or­di­na­tor, re­spec­tively, with the Col­lege’s Cen­ter for En­vi­ron­ment & So­ci­ety, and a small cadre of sum­mer re­search stu­dents each year.

In 2014, re­searchers lo­cated 90 nests in the re­stored grass­lands and suc­cess­fully filmed 32 of them re­sult­ing in 132 hours of video footage to re­view. In 2015, that num­ber jumped to 115 nests with 65 be­ing filmed. In 2016, Carr and the team lo­cated 119 nests, and this past sum­mer 103 nests.

“We would go out ev­ery morn­ing and ob­serve the field spar­rows and watch their be­hav­ior, and that would in­di­cate whether they had a nest,” Free­man said. “And our main goal was to be able to find the nest in or­der to be able to see if they be­came bet­ter par­ents as they aged.”

Carr, Gim­pel, and Small plan to pub­lish the re­search re­sults this win­ter. Pre­lim­i­nar­ily, Carr said, it ap­pears as though males do not feed chicks more as they age, although fe­males do.

“This is a lit­tle sur­pris­ing, since they live for so long, and they def­i­nitely learn and mod­ify their be­hav­ior. It’s sur­pris­ing that males don’t seem to im­prove since suc­cess of the nest re­ally de­pends on bi-parental care,” Carr said. “Age doesn’t seem to be a big con­tribut­ing fac­tor, but the sex of in­di­vid­u­als seems to be. Fe­males are lit­tle more at­ten­tive. And feed­ing rate is an im­por­tant driver of nest suc­cess.”

Carr and the team also be­gan a new, re­lated study this sum­mer, us­ing the same habi­tat and the same birds, but study­ing where the birds choose to nest as a de­ter­min­ing fac­tor in nest­ing suc­cess.

“We’re do­ing veg­e­ta­tion plots around the nests, char­ac­ter­iz­ing where they are in re­la­tion to a tree­line, for in­stance, and whether they’re be­ing eaten by a preda­tor or dy­ing from ex­po­sure or a me­chan­i­cal fail­ure of a nest just fall­ing over,” Carr said. “We’re ask­ing more ques­tions about field spar­row suc­cess and age — be­cause we want to take ad­van­tage of that vari­able while we can — but also how is their nest build­ing skill or place­ment vary­ing over time, if it is.”

For Free­man, the work was a first on many lev­els — her first in­tern­ship in the field, her first work­ing with a species like the spar­rows, her first liv­ing on her own in an apart­ment-type set­ting off cam­pus, in the field house where in­terns spend their sum­mer.

“I was able to do the things I learned at Wash­ing­ton Col­lege. I was able to put hands on,” she said. “And it also taught me a lot about pa­tience and how things aren’t go­ing to be the way you want all the time. There would be days when I wouldn’t find a field spar­row nest, and it was just in­ter­est­ing to see how stuff doesn’t al­ways go as you planned, and how you have to adapt and learn and kind of be think­ing on your feet.”

Jen­nie Carr, as­sis­tant pro­fes­sor of bi­ol­ogy, left, and Made­line Poethke, 2016, use scopes to spot field spar­rows in the re­stored grass­lands at Wash­ing­ton Col­lege’s Ch­ester River Field Re­search Sta­tion.

A nest full of young field spar­rows.

A pair of hun­gry field spar­row ba­bies wait with open mouths for food.

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