From the Field:

2009 Research Under Way

Nesting Success Research 

June 8th, 2009

As we reach the beginning of June, nesting activity increasing across the study sites is quite high and should near it’s peak over the next couple of weeks. The large amount of snow we received this winter resulted in excellent wetland conditions across most of our study sites with abundant shallow water everywhere. And the birds have clearly responded with a substantial breeding effort from most species. Northern Pintails were noticeably abundant early and continue to take advantage of all the shallow water across the landscape. Mallard numbers are also good and blue-winged teal and northern shovelers seem to be abundant across our study sites. Most mallard and pintails are either renesting or near hatch for their initial nest. We have had the first nests for mallards and pintails hatch across each of the crew areas. Study site 8 in the Stanley crew area has done well with 14 nests hatched thus far. In the Goebel crew area, study site 41 has had 8 nests hatch to date. Not surprisingly, both of these sites have significant amounts of grassland on the site and in the surrounding area. However, to date our crews of located 756 total duck nests which is nearly twice as many as were located by this time last year during dry conditions. Thunderstorms are beginning to roll across the prairies of North and South Dakota providing some much needed precipitation to help fuel growth of upland nesting cover provide some run-off to maintain flooding in temporary and seasonal wetlands. This week in From the Field, we will discuss the many factors in the birds favor during wet years like we have in 2009.

When wet conditions exist across the prairies as we have been blessed with in 2009, the birds can take advantage of several important factors that contribute to good production. First, with shallow seasonal and temporary wetlands flooded, invertebrate food production booms and the food resources are available to support a large breeding population of ducks. These shallow wetlands also provide for an abundance of pair territories so breeding populations increase dramatically. We’ll see how much when the U.S. Fish and Wildlife Service releases their May breeding survey estimates later this month. Additionally, this abundant food resource is important for birds that lose their first nest. Under wet conditions, they are able to quickly replenish their body reserves and lay another clutch. Once ducklings start to hatch, abundant seasonal wetlands provide ideal brood habitat with abundant invertebrate food and lots of emergent cover for the ducklings to hide in. As a result, duckling survival rates can approach 70 – 75% which could be nearly twice the survival rate during dry conditions. All of these advantages in concert facilitate booms in production when the prairies initially get wet like this year. We’ll see the best evidence of this when the breeding population estimates from next spring are tallied as many of the young birds produced this year return to breed.

We’ll continue to follow along with the crews as we watch one of those stellar years for duck production unfold. Despite prime environmental conditions several habitat trends remain disturbing like continued loss of native grassland and expiration of CRP grasslands The month of June is the time that most of the young will be produced during this breeding cycle here in the Dakotas. So please check back to see how things progress.