Breeding Phenology of
Anurans Found in the
frogs* (Rana sylvatica) begin
breeding. Their breeding season is
the earliest and shortest of any Wisconsin frog.
Their call is said to resemble a ducks quaking.
This species is possible, yet unlikely to be heard in the La Crosse River
March to Mid-May:
chorus frogs (Pseudacris triseriata)
begin breeding. Male chorus frogs
begin calling soon after and concurrently with wood frogs in areas where both
exist. Their call is said to
resemble a finger being run down the teeth of a metal comb. These frogs have been heard in the La Crosse River Marsh for
Peepers (Pseudacris crucifer) begin
breeding. Males of this species are
often heard calling in the marsh, and concurrently with western chorus frogs.
Their call is a high-pitched, singular “peep”.
March to Early-June:
leopard frogs (Rana pipiens) begin
breeding. Males are occasionally
heard calling in conjunction with peepers and chorus frogs. Their call is a very low-pitched “snore”.
They are relatively quiet callers and are sometimes drowned out by other
calling species. These frogs definitely exist within the La Crosse River
April to Mid-July:
toads (Bufo americanus) begin calling. In
areas where they exist, American toads are frequently the most numerous anuran.
During the breeding season, large groups of them are seen amplexing in
shallow water, surrounded by many strings of eggs.
Their call is a long trill, lasting several 5 to 10 seconds.
American Toads have been heard in the La Crosse River Marsh.
treefrogs (Hyla versicolor) begin
calling. These frogs are easy to
distinguish from other frogs in that they can climb sheer surfaces and have
large, sticky toe pads on the tips of their toes.
The call of a Gray treefrog is also a high-pitched trill, however, it
seems more melodic and is much shorter in duration than the American toad’s.
These anurans definitely exist within the La Crosse River Marsh.
Late May to Early/Mid-August
Frogs (Rana clamitans) begin calling.
Green frogs are similar in appearance to leopard frogs, but have no
spots. Their call resembles a
rubber band being plucked numerous times. Green
frogs have been heard calling for multiple years in the La Crosse River Marsh.
· Bullfrogs (Rana catesbeiana) begin calling. A bullfrog’s call is a deep, resonant “Ba-ruum, ruuum, ruuum” sound. The reports of these frogs in the marsh are sporadic and it is unlikely that they will be heard.