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Most species may at least occasionally be found under loose stones, boards, 
logs, bark, and similar cover. This is equally true in both terrestrial and 
aquatic habitats. Some species are rarely seen unless suitable cover is 
looked under. In places where little cover is available, good results may 
sometimes be obtained by placing boards, tar paper, and similar objects on 
the ground. Subsequent inspection of these will yield specimens. Care 
should always be taken to replace disturbed objects to their original position 
so that they will continue to offer suitable retreats for herptiles. Turtles 
under cover of vegetation or mud on the bottom of a pond may be detected 
by feeling for them with the hands or bare feet (see Lagler, 1943, p. 22). On 
land they may be discovered in piles of leaves and similar cover by ‘sounding’ 
with a wooden pole as described by Carpenter (1955). 
Amphibian breeding aggregations. Many amphibians appear at 
temporary ponds during the first warm days after the snow has melted. 
The earliest breeders may even start calling before the ice on the ponds has 
completely melted if daytime air temperatures have been warm enough. 
The most vigorous calling and breeding activity is usually at night. For 
some frogs and salamanders the breeding period is remarkably short — as 
little as two weeks elapsing between the arrival of the first individual and the 
departure of the last if the weather is consistently warm. Breeding frogs 
form large choruses which can be heard from some distance. The salamanders 
which breed in the same temporary ponds usually arrive at the same time as 
the first frogs are calling. The early breeding frogs are followed by other 
species as the weather gradually becomes warmer, and usually several 
species of frogs may be heard on the same night. The latest frogs to breed 
are those which lay their eggs in permanent water. These do not start 
to call in appreciable numbers until late spring or early summer. 
In the grassland regions of the prairie provinces and British Columbia, 
many amphibians breed only during or after heavy rains in the late spring 
or early summer. They are difficult, often impossible, to find except during 
this brief (often only one or two nights) period. In exceptional years when 
no heavy rains fall during this time, they may not breed at all. 
Night is the best time to collect breeding amphibians, and a headlamp 
or flashlight ( see below) is essential. Most of these species are difficult or 
impossible to approach in the daytime, and some are active only after dark. 
Other amphibian aggregations. Amphibian eggs are usually laid in 
large numbers, and often the percentage of larvae which develop to trans- 
formation is high. The developmental rate of species that lay in temporary 
ponds is rapid, so that the first transforming frogs are ready to leave the 
pond by early summer. Often large aggregations of tadpoles, salamander 
larvae, or transforming individuals can be found at or near a pond margin 
in the open or under suitable cover. Recently transformed individuals of 
one species or another may be found at the margin of aquatic habitats 
throughout the summer and early fall. Often species that were overlooked 
during their breeding season may be identified from larvae or transforming 
individuals. 
Hibernating dens. In the spring or fall, snake dens may occasionally 
be located. During the first warm days of spring, snakes emerge from such 
hibernating sites to sun themselves at or near the entrance. Dens are often 
in rocky outcrops on south-facing slopes where there is access to a dry 
location below frost penetration. Often one den serves as winter quarters 
