Atlas data

Expanding woodpeckers

Last spring, Greg Hanisek wrote a blog post about the growing range of yellow-bellied sapsuckers in Connecticut. During the last breeding atlas, in the 1980s, the species was largely confined to the northwest corner of the state, with only scattered records of possible breeding elsewhere.  Since then, the species is known to have spread south and east, but exactly how much was unclear. Continue reading

Can we confirm robins in every block?

Last summer I wrote a blog post highlighting 12 species that it should be possible to confirm as breeders in almost all atlas blocks.  That list is reproduced here:

1. Song sparrow
2. American robin
3. Gray catbird
4. Black-capped chickadee
5. Mourning dove
6. Northern cardinal

7. Blue jay
8. House finch
9. Common yellowthroat
10. House sparrow
11. Chipping sparrow
12. Tufted titmouse

 

Continue reading

Where have all the parids gone? (Answer: probably nowhere)

The summer of 2018 proved to be a really great start for the atlas, but whenever we present last year’s data we are constantly pointing out that comparisons to the first atlas need to be made with care. In part, we make these cautions because the data are still being reviewed to ensure we’ve made no errors. But, the main reason is simply that the historic data come from five years of field work, not just one. Continue reading

Early spring targets: ruffed grouse

Spring is well and truly here, and there are signs of breeding all around. Species that can be confirmed as breeders should be reported to the atlas, but what about everything else that you see? At this point there are more than a dozen species that are within safe dates, so any time you see any of the species on the list below in suitable nesting habitat, please report them. This week, we are planning a series of posts to highlight some of these species and to contrast the data we gathered last year with information from the first breeding bird atlas in the 1980s. As we’ve cautioned before, all 2018 data are preliminary as we are still checking records and fixing known errors, but the information provides a good snapshot of what we’ve learned so far. Continue reading

The trouble with safe dates …

The single most common cause of confusion during last year’s summer atlas data collection, was the use of safe dates. The important thing to remember is that these dates are based on the timing of migration and other non-breeding season movements, and do not describe the period during which breeding occurs. The goal is to filter out possible and probable records that could involve birds that are just passing through a block and will nest elsewhere. For example, ducks can be seen doing courtship displays right now.  Many of these birds, however, will breed 100s of miles from where they are being seen right now and do not represent Connecticut nesting birds. Indeed, some species that are commonly seen displaying in spring have never bred in Connecticut. Continue reading

Check your local swamp for herons

Although great blue herons can be found in the state throughout the year, many migrate south during winter, and those that remain tend to retreat to the coast as freshwater wetlands freeze over. Several posts on the ctbirds listserv this week have shown that great blues are starting to return to their nesting colonies, and the next couple of weeks – before the leaves start to emerge – will be an ideal time to check all the swamps in your atlas block for active nests. Continue reading

Ravens

Over the past couple of weeks, ravens have been a regular sight at UConn. Displaying from the roof of the visitor’s center, wheeling over the parking garage, and yesterday I even heard one while sitting in my office. The species has nested in a farm building near the university’s Depot Campus for a couple of years and is seen throughout the area, but this is the first sign that they might nest right on the main campus. Continue reading