Six gull species at the Hidden Hollow Landfill

In early January we made a trip to the Hidden Hollow Landfill, north of Boise in the foothills. While a landfill may seem like a non-traditional place to spend your leisure time, this landfill is a great spot to look for rare gulls in the winter. This winter was no different, and we headed up on January 10 to see if we could find anything out of the ordinary. We weren’t disappointed at all, and found six species of gulls, including two Lesser Black-backed (both adults), one Mew (adult), several Herring (3 adult, one 2nd winter), one Thayer's (adult), as well as high numbers of the usual California and Ring-billed.

Mew Gulls are quite similar to Ring-billed Gulls, but lack any significant marking on their bills, though sometimes very faint markings are still present.

Mew Gull (center) at Hidden Hollow Landfill, Ada County. January 10, 2015.

The Lesser Black-backed Gull is unique for the combination of a light iris, black and red on the gonydeal expansion (bulge at the end of the bill), dark black back, and smudgy head.

Lesser Black-backed Gull (center) at Hidden Hollow Landfill, Ada County. January 10, 2015.

California Gulls are quite common, and are a bit larger than a Ring-billed Gull, with both red and black dots at the end of their bills, and are sometimes a bit darker gray across the back than Ring-billeds.

California Gull at Hidden Hollow Landfill, Ada County. January 10, 2015.

Herring Gulls are quite large, and have pink legs, light irises, a single red dot on their bill.

Herring Gull (center) at Hidden Hollow Landfill, Ada County. January 10, 2015.

In this shot you can see the Lesser Black-backed and Mew Gulls in the same shot.

Lesser Black-backed Gull (center) and Mew Gull (upper left) at Hidden Hollow Landfill, Ada County. January 10, 2015.

Lesser Black-backed Gull (center) at Hidden Hollow Landfill, Ada County. January 10, 2015.

Lesser Black-backed Gull at Hidden Hollow Landfill, Ada County. January 10, 2015.

Lesser Black-backed Gull at Hidden Hollow Landfill, Ada County. January 10, 2015.

And this shot confirms that we had two Lesser Black-backed Gulls, since you can see both in the same shot.

Lesser Black-backed Gulls (lower left and upper right) at Hidden Hollow Landfill, Ada County. January 10, 2015.

I usually don’t get too ambitious with juvenile gulls, but some aren’t too hard to ID. Here’s an adult and a second winter Herring Gull, standing side by side for comparison.

Herring Gulls (adult and 2nd winter) at Hidden Hollow Landfill, Ada County. January 10, 2015.