Saturday, April 26, 2014

The First Male

The first bird was back this morning!  The wrens haven't started building nests yet but this morning one male was singing around the A field.  The first males to come back have their pick of territories and they often spend a couple days wandering around before they settle down.

I was only able to see one leg of bands, but based on the colors it's very likely this is the same male who nested in the same area last year.   Bk/wh, gn/al male was first banded as an adult during the summer of 2011 and is featured in my favorite photo of a house wren below.  In 2011 he had a rough time.  He built a lop-sided nest and tried for several months unsuccessfully to attract a female.  In 2012 he returned again and made two nesting attempts, but they were both eaten by predators.  Last year he was the second male to come back from the migration and things went much better.  He had two nests with the same female and raised one to fledging successfully.  He's leading the wave again this year and at least 4 years old he'll likely be one of the older males at the field site this summer.

    Bk/wh, gn/al male from 2011.  It's likely this was the first male I heard singing this morning.

Tuesday, April 22, 2014


Right now is the awkward part of the season where the house wrens have been spotted in Michigan but have not yet shown up at the field site.  Although the wrens are so far silent, other birds are in full swing.  Both chickadees and flying squirrels have claimed some boxes as their own.

A chickadee nest starting at territory 19

A flying squirrel nest at territory 29
 The flying squirrel living at territory 29

Saturday, April 19, 2014

Tracking the Migration

How do you know when the birds are here?  This is a challenging question at the start to every field season.  The house wrens in Michigan spend their winters down in the southern United States and every year they arrive at a slightly different time depending on how the weather has been across the country.  

Here is where citizen scientist efforts are particularly helpful to researchers like me.  Cornell University runs the eBird program ( where birders across world can submit lists of any birds they see.  Checking eBird every days lets me watch the migration in real time.  Citizen scientist efforts like this are extremely useful for ornithologists like myself.  There's no way I could hope to track the migration by myself!  When house wrens are sighted in Michigan, I know they might show up at my field site any day.  Based on the data so far, I expect them to be here by the beginning of next week!

 eBird view of house wrens from March-Apr 19th.  Purple squares show all the places where house wrens have been observed.  The darker the purple, the more times house wrens were seen.

Box Day!

Preparations are in full swing for the arrival of the house wrens!  Boxes went up at Lux Arbor on the 8th in anticipation of their arrival.  Boxes are great homes for house wrens and chickadees but they're also favorites of mice and  flying squirrels.  We take down the boxes each winter to help minimize destruction by these mammals.
A pile of boxes waiting to go out into the field

Box set up at territory C4.  The early part of the season is my favorite since it's so easy to see through the vegetation.  Good for spotting house wren bands!


A male house wren poses for the camera during the summer of 2011

My names is Cara Krieg and I'm a graduate student at Michigan State University in Tom Getty's lab.  This summer I'll be blogging about the research the undergrads in our lab and I will be doing a local population of house wrens.  For more information about my research, check out my professional website at

So why "birds in boxes"?  First, I study house wrens, a small species of song birds that needs to find a tree
hollow or nest box to build their nest.  They're great for research because if you put out boxes, the birds will come to you!  Second,  I hope that my work will help blur the boundaries of the boxes we put around male and female behavior.  In human society we have certain stereotypes about how men and women should behavior.  Men are seen as more competitive, more likely to get into a fist fight in a bar or be into sports, whereas women as seen as more nurturing and maternal, more likely to be focused on relationships and to be nice to your face.  In the scientific world, scientists have similar expectations.  Male animals are a lot more likely to be in fierce fights or to have elaborate ornaments and behaviors to attract the attention of females.  However, as anyone who's paid attention to people knows, reality is a lot more complicated than these boxes.  It turns out nature is a lot more complicated too!  I focus on two traits in female house wrens- female-female aggression and song- that have historically been considered male behaviors.  I'm trying to understand why these female behaviors exist, how they differ from males, and maybe how males and females are more similar than we first thought!