Bird Photos

Ivory-bill (top), Pileated (bottom)

Pileated (top), Ivory-bill (bottom)

Passenger Pigeon male (top), Passenger Pigeon female (bottom)

Passenger Pigeon (top), Mourning Dove (bottom)

"Cincinnati Warbler"

Eskimo Curlew

Prairie Chicken

Razorbill

Great Auk

Great Auk egg

Dusky Seaside Sparrow

Eskimo Curlew

Eskimo Curlew in plastic bag for protection against insects

Eskimo Curlew in plastic bag to protect against insect damage

Eskimo Curlew feet & tags

Carolina Parakeet

Ivory-billed Woodpecker

Ivory-billed Woodpecker (top), Pileated Woodpecker (bottom)

Pileated Woodpecker (top), Ivory-billed Woodpecker (bottom)

Ivory-billed Woodpecker

American Kestrels in Ohio

What a difference a year makes when it comes to understanding bird populations. Take, for example, the American Kestrel. Some Ohio naturalists have asserted that American Kestrels are declining in Ohio and base those assertions on anecdotal observations, data from neighboring states (with fairly different landscape features), or on the wrong kind of data sets (i.e. breeding bird atlases). Well, over a year later it looks like American Kestrels are probably doing just fine in Ohio.

Since one of the data sets that some of these naturalists are using is the 2nd Ohio Breeding Bird Atlas, I’ll start with that one first.

In 2007 the Breeding Bird Atlas map for American Kestrels looked like this:

Of course it looks pretty sparse, which led a few naturalists to think that kestrels must be declining in Ohio. Especially when compared to the first breeding bird atlas map for Ohio (see below). However, when you consider that 2007 was only the second year of data collection, and the first atlas was based on five years of data, you can start to see a flaw in the logic of comparing the two.

Additionally, most breeding bird atlases do not quantify bird abundance (the number of individuals), but rather just the distribution of birds across a geographic area (though there are some species for which abundance data is collected). This means that each square could hold anywhere from 1 bird exhibiting breeding behavior to 1 million birds exhibiting breeding behavior, and it would be recorded the same way on the map. For many species there is little to no quantification of the number of individuals within a block. As a result an atlas is not really effective for quantifying bird population changes for some species, except maybe on a rough scale.

Now if you look at the atlas map for 2008 you’ll see a rather major difference between the 2007 map.

It’s definitely filled in quite a bit more since the previous year. It’s starting to look a lot more similar to the map from the first atlas (see below). Does this mean that American Kestrels experienced a population explosion over the course of a year and spread throughout the state? No. Of course it doesn’t. What it means is that a third year of data collection allowed atlasers to cover more areas throughout the state and detect more kestrels. In fact, given another two years of data collection it will be easier to compare the 2nd atlas to the 1st and assess if there have been any changes in terms of breeding occurrences. However, it’s still a little premature to try and compare the current data set to the first data set.

It's also important, when looking at the map above, to consider the amount of effort (amount of time in the field by observers collectively) that has been invested in atlasing and where. Below you'll see a map illustrating the amount of effort that has been invested in atlasing in Ohio. Lighter shades of blue represent less effort and darker colors represent more effort. Areas of white are areas that have not been surveyed yet. More effort is still needed in many areas to help determine where Kestrels are breeding in the state.

Map (above) from the first Breeding bird atlas (1982-1987) for American Kestrels. It's important to understand that dark colors do not represent greater abundance of kestrels, but rather just confirmed breeding whereas green squares are where it was suspected that kestrels were breeding based on various indicators.

Now if we really want to know what’s happening to American Kestrels it’s better to look at data sets that actually look at trying to quantify population numbers. Two of our oldest data sets are the Christmas Bird Count and Breeding Bird Survey. When we look at these data sets we see something entirely different for American Kestrels in Ohio.

Breeding Bird Survey data suggests that American Kestrel populations may be stabilizing relative to Red-tailed Hawks, which are often found in similar habitats as kestrels. In fact, increasing Red-tailed Hawk populations may be affecting kestrel populations. (I have a hypothesis on why and how this might be happening, but I’m still looking for the appropriate data set to use to evaluate my hypothesis.)

Christmas Bird Count data suggests that winter kestrels are potentially declining. However, this could be due to a number of factors. It could be that more kestrels are migrating out of the state during the winter months. It could also mean that fewer kestrels are migrating into Ohio during the winter. However, over-wintering Red-tailed Hawks continue to increase. Again, increasing populations of Red-tailed Hawks could also be the culprit for changes in kestrel populations, especially during winter months when prey availability decreases, and there is greater competition between predator species (especially with the influx of raptors from the north, like Northern Harriers and Rough-legged Hawks).

Fortunately, the BBS data doesn’t show the dramatic decline that is occurring in the winter months which would suggest that the resident, or at least breeding, population of American Kestrels in Ohio is probably doing just fine and adjusting to changing land uses (i.e. increasing urbanized landscapes) and greater competition from a highly adaptive species (Red-tailed Hawks).

It will be interesting to see what the final Breeding Bird Atlas will look like for kestrels in Ohio, but understanding how populations of birds are doing can help focus conservation effort on species that are critically declining versus those that might be doing just fine. Unnecessarily claiming a species is declining based on faulty information can potentially distract important conservation efforts from those species that really need assistance.

male Ring-necked Pheasant--Killdeer Plains W.A. near Harpster, OH--11.28.2008

This is an old photo of the Snowy Owl that was found near Wilmington, OH in November of 2000.
This photo was scanned in from a printed photo. You can compare this bird to the Preble County bird pictured below (scroll down).

Snowy Owl--Preble Co., OH--11.29.08

Snowy Owl--Peble Co., OH--11.29.08

Snowy Owl--Preble Co., OH--11.29.08

Snowy Owl--Preble Co., Ohio--11.29.08

Snowy Owl--Preble Co., OH--11.29.08

Getting in a good scratch behind the ears

Taking a short nap

Stretching and ruffling some feathers

Settling back in for another nap

American Goldfinch--Indianapolis, IN--08.02.08

I know I normally post bird photos here but I wanted to post these photos from a trip I took with a frind during the holiday weekend to The Wilds, located in southeastern Ohio. I hadn't been on the inside of the park itself for a tour in quite a few years, so it was nice to take the opportunity to take a friend to visit the park. I did some light birding while there, but didn't have the time or opportunity to try and get photos of the birds. Enjoy these photos from the trip instead.

male Cheetahs--The Wilds--07.05.08