In long run, flood may benefit Boulder County, Colorado, USA, native wildlife-Still, burrowing animals (like herps) hit hard by September deluge – via Herp Digest

By Stephen Jones and Ruth Carol Cushman, Daily Camera 

11/03/2013 

During the height of the September rainstorms, an Eldorado Springs resident found a mink holed up in her kitchen, and neighbors saw rattlesnakes swimming in the town's sewage treatment pond.

Dozens of drowned prairie dogs turned up on city of Boulder and Boulder County open space properties, and a few prairie dog colonies located in floodplains appear to have been entirely depopulated. Some prairie dog burrows remained flooded for several weeks after the storms.

Preliminary reports suggest that burrowing animals, including rodents and snakes, may have suffered the greatest losses during the September rains. Many animals probably drowned in their burrows, while others were swept away by the raging waters or killed by predators.

Federally threatened Preble's meadow jumping mice were about to enter hibernation as the deluge struck. Their burrows lie in floodplains that were saturated by the rains, so open space ecologists fear that many may have drowned. One hiker did find several dead mice of undetermined species near the high water mark along Bobolink Trail.

Several people found tiger salamanders and toads in their window wells. One observer reported dozens of small dead snakes littering Colo. 93 during the height of the downpours.

Greenwood Wildlife Rehabilitation Center east of Lyons admitted baby squirrels that may have been washed away from their nests, along with several emaciated rock pigeons. A few observers found dead birds on the ground, including a mourning dove, a crow, two magpies, a Bullock's oriole and a house finch. Some of these birds may have died of hypothermia after the feathers became soaked.

However, some birds probably benefited from the proliferation of mosquitoes and other insects after the deluge. A couple of weeks after the storms, we saw flocks of black-capped chickadees and Audubon's warblers feasting on swarms of mosquitoes at Sawhill Ponds Wildlife Area.

On Shanahan Ridge in south Boulder, we marveled at the sight of butterflies and moths flitting across the grasslands within hours after the rains subsided. Moths commonly shelter under tree bark and building eaves during rainstorms, but many of the butterflies must have stayed dry by clinging to the undersides of hanging leaves and tree branches.

Within days after the storms, we found more than a dozen recently emerged common buckeye butterflies on Shanahan Ridge. The chrysalises of these locally uncommon beauties may have come through the deluge in such good shape because buckeyes evolved in the southeastern United States, where autumn downpours frequently occur.

In the long run, alteration of prairie streams and floodplains may benefit native wildlife populations. Along Coal Creek south of Boulder, the raging waters thinned out overcrowded groves of cottonwoods and willows while dramatically widening the stream channel and depositing immense piles of sand and silt.

This natural thinning of riparian woodlands will create more space for grassland-nesting songbirds while reducing nesting opportunities for non-native eastern species. The piles of sand will provide nurseries for cottonwood seedlings, adding age and height diversity to streamside woodlands. Finally, the widened stream channel will enable the creek to meander more freely, creating deep pools for native fish and amphibians.

For years, ecologists have been telling us that periodic scouring floods are essential to maintaining ecosystem health in prairie stream corridors. Only time will tell how local wildlife populations respond to this most recent flooding event.

Stephen Jones and Ruth Carol Cushman are authors of "Wild Boulder County" and "The North American Prairie."