Thanks, glad you all enjoyed the photos. Winter just makes it more fun to see the spring breeding migrations!
Joan, that is about it for my habitat shots. This is only the second time I have found H. scutatum. Good luck on your searches!
Ian, that's a very interesting question. Without a doubt seasonal variation in environmental conditions influences aspects of amphibian breeding. There have been a couple studies that have looked for long-term trends in changes in phenology in amphibains, with variable results.
For example:
Amphibian breeding and climate change
Blaustein AR, Belden LK, Olson DH, Green DM, Root TL, Kiesecker JM
Source: CONSERVATION BIOLOGY 15 (6): 1804-1809 DEC 2001
Abstract: Climate changes may be influencing the breeding patterns of certain organisms. Effects oil breeding activities could eventually lead to significant changes in population structure that may be reflected in population declines of species that are especially sensitive, such as some amphibians. Thus, climate changes may have affected the timing of breeding in some European amphibian species. To further test whether amphibian reproductive cycles in temperate countries are responding to climate changes, we conducted all analysis of the breeding phenology of four species of North American anurans for which we have long-term data sets. Populations of at least two of these species have been declining, and it has been suggested that they and other amphibians may be especially sensitive to climate change, Our results suggest that climate change has not influenced the timing of breeding in amphibians in North America. At one site, in Oregon, a trend (non-significant) for western toads (Bufo boreas) to breed increasingly early was associated with increasing temperature, At four other sites, however, neither western toads nor Cascades frogs (Rana cascadae) showed statistically significant positive trends toward earlier breeding. At three of four of these sites, breeding time was associated with warmer temperatures. The spring peeper (Pseudacris crucifer) in Michigan did not show a statistically significant trend toward breeding earlier but did show a significant positive relationship between breeding time and temperature. Fouller's toad (Bufo fowleri) in eastern Canada did not show, a trend toward breeding earlier, and there was no positive relationship between breeding time and temperature. It did however, show a strong but statistically insignificant trend toward breeding later. The broad pattern emerging from available studies is that some temperate-zone anuran populations show a trend toward breeding earlier, whereas others do not. It is important to track the breeding patterns of amphibians with long-term data sets to morefully understand how we can manage threatened populations.
Climate warming and calling phenology of frogs near Ithaca, New York, 1900-1999
Gibbs JP, Breisch AR
Source: CONSERVATION BIOLOGY 15 (4): 1175-1178 AUG 2001
Abstract: Because ambient temperature strongly influences reproduction in frogs, the seasonal timing of frog calling provides a sensitive index of biotic response to climate change. Over the last century, daily temperatures increased during 5 of the 8 months key to gametogenesis in frogs and toads near Ithaca, New York (U.S.A.). Earliest dates of calling frogs recorded by Albert Hazen Wright between 1900 and 1912 near Ithaca were compared to those from the New York State Amphibian and Reptile Atlas Project for 1990-1999 for the three counties surrounding Ithaca. Four species are now calling 10-13 days earlier, two are unchanged, and none is calling later. The data suggest that climate has warmed in central New York State during this century and has resulted in earlier breeding in some amphibians-a possible first indication of biotic response to climate change in eastern North America.
thanks.