Common Yellowthroats prepare to head south
Published at | Updated at
Last week while traveling through Market Lake marshes, I heard the singing of dozens of Common Yellowthroats as they began to congregate for their fall migration south. The males with their black masks stood out as they set on top of cattails or bulrushes and called while the females blended in the thick cover.
They are part of the warbler family which start gathering around the first of August before most of them migrate to Mexico, Central or South America. Yellowthroats are numerous in the marshlands of Idaho and many of them nested in the Market Lake and Camas National Wildlife Refuge areas. Whereas many of the Wilson’s and Yellow warblers nested in tree and willow thickets.
The yellowthroats are common through most of the United States and was one of the first species to be cataloged in 1766 on the east coast by Linnaeus. It is another hard bird to see, as they blend in well and hide in the thick growths of cattails and other matted marsh vegetation.
The males migrate to Southeastern Idaho first and each develop a nesting territory and as the females show up, they create a loose bond. Males defend their territory from other males, but each territory have very close neighbors creating battles between them.
Once a couple bond has been established, the female builds the nest which is well concealed, some even sporting a canopy over the nest. The problem for the nesting yellowthroats is they are often targeted by Brown-headed cowbirds to remove the original eggs and lay their own to replace them. If a female is smart enough to recognize the odd egg, they may build another nest on top of the original. Some yellowthroat nests have been found to have a third nest built on top, destroying the “parasite” eggs from the cowbirds.
They usually only raise one brood each summer from one to six babes, but cowbirds are not their only nemesis in the marsh. Northern harriers, Short-eared owls, American bitterns, Black-crowned night herons, mink and weasels all prey on the masked birds. One day during nesting period this summer, I watched as about 15 males gathered to dive bomb an area at Market Lake. They had quit fighting between themselves to join forces in attacking a long-tailed weasel. It left quickly – the noise was probably worse than their bites.
These warblers eat seeds, insects, fruit like currants and skunk berries that grow low to the ground, but they seem to prefer different kinds of seeds located in the marsh areas. I have even seen them picking the seeds out of cattails.
All indications point to them leaving soon. I love watching them in the cattails of Market Lake. They can be a lot of fun. Be careful out in the wilds and around wild animals. Looks like the bears are really getting active as the put-on weight for the winter. Watch out for them.
By the way, the Idaho Department of Fish and Game finished gill netting on Ririe Reservoir and did not find many mature kokanee. But they did find those that were planted in June are up to four and a half inches and appear to be surviving very well. Hopefully by January we will have some up to eight or nine inches to harvest during ice fishing. They said that in the gill netting on Island Park, the numbers on mature kokanee were much better than Ririe.