Wednesday, June 20, 2012

Dickcissels in Dearborn

(Edited 25 Jun with new data)
There are at least a dozen Dickcissels (maybe more) in the wildflower fields at Ford Road and Mercury. This is the field marked "8" on our page of Ford fields. Note that the fields are marked "No trespassing," so if you visit, please scan from a roadside and be careful of traffic. I first heard these birds on 18 June. My husband Darrin O'Brien saw a bird carrying food later that day, indicating that they are probably nesting. Our survey on 24 June located at least 10 singing males and 2 females. There are also dozens of Savannah Sparrows in this field.

On 20 June, Jim Fowler and Dave Washington located two more Dickcissels in the fields on the south side of Lundy Parkway (field number "6"). Darrin had 9 there on 21 June, and we had eight on 24 June.

The two small wildflower fields ("1a" and "1b") have two birds. So, at least around two dozen Dickcissels in Dearborn!

The last Dickcissel record in Dearborn was from 1 July 1907! The only other confirmed record I could find when researching my book on Dearborn birds was a flock near the Rouge River from 30 July 1899. Three of these birds were collected, and I have examined the specimens in the University of Michigan Museum of Zoology in Ann Arbor. All of these records are attributed to "Springwells." Dearborn's present borders were established in 1929; prior to that portions were known as Fordson and/or Springwells. I believe the 1907 record was from somewhere near what is now Rotunda and Schaefer in Dearborn. The route of the Rouge River has also been altered since 1899, but I think that the 1899 specimens are also from Dearborn.

Long time, no see! The last Dickcissel record from Dearborn was in 1907.This male, 20 June 2012.
Photo by Cathy Carroll, used with permission, all rights reserved.

Female Dickcissel, Dearborn, 20 June 2012.
Photo by Cathy Carroll, used with permission, all rights reserved.

Dickcissels are specialist birds that depend on grasslands. They are known for their unpredictable, semi-nomadic movements, in particular outside of their core prairie habitat in the Great Plains. It's hard to know where they'll show up from year to year.  While they can be quite adaptable and will use non-prairie grassland habitats, the loss of native prairie has been a factor in dramatic population declines. These little birds winter far into South America, mostly in the grasslands of central Venezuela. They winter in huge flocks and can be considered pests on grain farms. They are hunted and poisoned regularly, which no doubt has contributed to declines in their numbers.

The wildflower fields the Dickcissels are using have a high diversity of herbaceous plants which are required by the birds for song perches and nesting substrate. In the great photos above, by Cathy Carroll, the birds are perched on Gray-headed Coneflowers  (Ratibida pinnata), a wonderful native wildflower. The wildflowers also provide for a wide diversity and abundance of insect prey, especially grasshoppers and butterfly and moth larvae, which are needed to raise their young.

Many of the fields planted by Ford Motor Company are sunflowers or hay fields. Those that have wildflowers are the least manipulated by mowing or disturbance and have the most interesting birds. Perhaps this will encourage Ford to convert more of the fields to wildflowers!


Jerry Jourdan said...

Wonderful news, Julie! I'll let you know if I get any photos this weekend.

Dimas Pioli said...

Gorgeous birds!!! Great to know!!!