The life of a tree in a wetland is never easy, frequently changing water levels and limited soil oxygen will kill all but the hardiest or best adapted tree. Frequently, trees on a wetland border, which are not particularly suited for wetland life die, but still play a surprising role in wetland ecology.Why are snags the zombies of wetland? - Despite being dead, they still teem with life!
The life of a tree in a wetland is never easy, frequently changing water levels and limited soil oxygen will kill all but the hardiest or best adapted tree. Frequently, trees on a wetland border, which are not particularly suited for wetland life die, but still play a surprising role in wetland ecology.
Over time, the dead trees, or snags, become homes for myriad insects from termites to ants, attracting woodpeckers. The Pileated woodpecker is one of first that come to mind; the powerful bird makes a distinctive rectangular and deep cavity during their search for insects, as seen in the photo I took this summer, below. Pileated woodpecker holes can be a food long and half as deep. After ferreting out all the available insects, the woodpecker will abandon the hole for others to use as shelter; it is estimated there are more than 30 species that rely on snags for shelter or food, including flickers and brown creepers which shelter in the holes or bark of snags. Pileated woodpeckers also nest in snags, the nest construction usually takes 3-6 weeks, and ranges between 10-24 inches deep.
Bats, and other small animals also use the peeling bark for shelter, and hollow snags are used by larger creatures ranging from owls, raccoons and even bears for protection from the elements.
Submerged snags are no less valuable, the limbs and trunks are less visible, but are utilized by fish and amphibians for shelter, concealment and spawning.
Sources and Further Reading:
Snags for Wildlife
SPECIALIZED HABITAT CONSIDERATIONS FOR NONGAME BIRDS -SNAG MANAGEMENT Keith E. Evans and Richard N,Conner
DeGraaf, R. 1978. New life from dead trees. Natl. Wild. 16(4):28-31
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