▁garden ▁p onds ▁to ▁spawn . ▁Where ▁conditions ▁are ▁har sh er , ▁such ▁as ▁in ▁the ▁Al ps , ▁they ▁emer ge ▁as ▁late ▁as ▁early ▁June . ▁Common ▁fro gs ▁hibernate ▁in ▁running ▁waters , ▁mud dy ▁bur rows , ▁or ▁in ▁layers ▁of ▁decay ing ▁leaves ▁and ▁mud ▁at ▁the ▁bottom ▁of ▁p onds ▁or ▁la kes ▁primarily ▁with ▁a ▁current . ▁The ▁o xygen ▁u pt ake ▁through ▁the ▁skin ▁suff ices ▁to ▁sust ain ▁the ▁needs ▁of ▁the ▁cold ▁and ▁motion less ▁fro gs ▁during ▁hi bern ation . ▁ ▁Re production ▁ ▁During ▁the ▁spring ▁the ▁f rog ' s ▁p itu it ary ▁g land ▁is ▁stim ulated ▁by ▁changes ▁in ▁external ▁factors , ▁such ▁as ▁ra inf all , ▁day ▁length ▁and ▁temperature , ▁to ▁produce ▁h orm ones ▁which , ▁in ▁turn , ▁stim ulate ▁the ▁production ▁of ▁sex ▁cells ▁- ▁eggs ▁in ▁the ▁females ▁and ▁s perm ▁in ▁the ▁male . ▁The ▁male ' s ▁nu pt ial ▁pad ▁also ▁sw ells ▁and ▁becomes ▁more ▁heavily ▁p ig ment ed . ▁ ▁Common ▁fro gs ▁bre ed ▁in ▁shall ow , ▁still , ▁fresh ▁water ▁such ▁as ▁p onds , ▁with ▁sp aw ning ▁comm encing ▁som etime ▁between ▁March ▁and ▁late ▁June , ▁but ▁generally ▁in ▁April ▁over ▁the ▁main ▁part ▁of ▁their ▁range . ▁The ▁adult s ▁con greg ate ▁in ▁the ▁p onds , ▁where ▁the ▁males ▁comp ete ▁for ▁females . ▁The ▁court ship ▁rit ual ▁involves ▁no isy