A couple of years ago, we took a trip out to the Kern National Wildlife Refuge. It was a little late in the spring, so unfortunately we had just missed the majority of the birds. Flooding of the habitat begins in October to coincide with the arrival of migrating waterfowl from the north, so the best time to visit is from October to March. However, when we visited in April, there were still plenty of birds there that hadn’t left yet.
The Kern National Wildlife Refuge is one part of the larger National Wildlife Refuge System, which provides crucuial waterfowl breeding habitat in key areas across the nation, as well as Alaska.
The Kern NWR was established in 1959. In the early years, water had to be pumped from deep wells or purchased from local water districts, but eventually both options became cost prohibitive.
It wasn't until the Central Valley Project Improvement Act was passed in 1992 that the refuge was provided with a reliable annual water supply.
The refuge is a bit over 10,000 acres; anywhere from 2000 to 5000 acres are flooded over a 3 to 6 month period to provide food, cover, and nesting habitat. Wetland management is determined by how much water and at what time of year that water will be available.
Seasonal marshes have water less than 4 feet deep and about a 50/50 ratio of open water and emergent wetland vegetation.
Providing hunting opportunities for waterfowl is one of the functions of the refuge system. There is a limited waterfowl hunting season from October to January.
Water is delivered through canals and ditches that are regulated by screw gates and flash board risers. Water is one of the most important resources on the Refuge.
Tule marshes were once common in the Southern San Joaquin Valley, but most of these wetlands were lost due to flood control projects and agricultural demands. The tule marsh provides habitat for nesting birds, as well as some waterfowl.
Wetland habitats are maintained through February, at which point a slow draining begins.
In the spring, some wetlands are drawn down to about 2" of water to provide shallow water/mud flat habitat for migrating shorebirds.
Some areas will be irrigated during the late spring and early summer to encourage plant growth to provide food for the migrating waterfowl the following fall.
There is an 6.5 mile auto-tour you can take around the refuge, and stopping and getting out of your car is allowed.
Visit the Kern National Wildlife Refuge online: http://www.fws.gov/kern/refuges/kern/