It is just after six o'clock in the evening on a cool, cloudy day, and the Chorus Frog voices are silent. They were calling "grri-i-i-i-i-i-ik" this afternoon. This pond is a special discovery in our Chorus Frog survey, as they haven't been heard east of Ottawa since the 1960's.
We've found during the past four days of warm weather survey work to the west that it seems that Renfrew/Castleford is now the northern range limit of the Ottawa Valley population. The model that suggests itself for this 20km
retraction of the range since the 1984-1996 period, is that increased drainage and increased field size, both before and after those dates, had isolated populations, and that they were killed off by the 1999 and 2001 droughts, but lacking wet corridors for dispersal, couldn't recolonize. In the same vein, but on a larger scale, Dave Seburn has been failing to hear Chorus Frogs at sites in Ontario east of Ottawa where they'd been heard in the past, so after leaving Renfrew we turned SE, toward an engagement at the Russell Library, and cruised along Hwy 17/417, recording "driveby" choruses, including two of Chorus Frogs, and hearing them calling quietly at a Cattail-ditch place where I had randomly stopped to cellphone - and hearing a few Chorus Frogs at a number of spots west of Ottawa, but none to the east.
Fred had earlier been fretting what a recovery plan for Chorus Frogs might look like, since a simple "revert to the landuse practices of the 1950's", while easy to draw up, and deliciously compact, might not be widely popular. But what we've found here north of Russell, is a island of 1950s style land use, on what was probably an island in the Champlain Sea...