by Kim Maley, Park Interpreter , Friends of Silver Falls State Park
Nature is amazing! Every living thing on earth has basic needs in order to be successful in this survival game. Everything needs energy (food), habitat, and to somehow secure the next generation. Overcoming obstacles to achieve this is one of Nature’s best skills! One of the clever adaptations developed to address seasonal food scarcity, for example, is to simply sleep through the lean months!
Silver Falls is home to several of these nature nappers. A few fun tidbits about two of my favorites:
BATS:
Little Brown Bat
Myotis lucifigus
All bats in North America have a strict insect-only diet. Not a single blood-sucker in the bunch! (Those cute little vampire bats live only in South America and only drink a tablespoon or so a day anyway and with zero supernatural side effects) Our bats, on the other hand, have nothing to eat during the winter; so they sleep! The females hibernate together in a “hibernacula” leaving the males to fend for themselves in small groups or independently.
Now wait. Gestation for Little Brown Bats (Myotis lucifigus) is 50-60 days. A 6-month gender segregation seems problematic from a reproductive perspective. But bats have an even more impressive adaptation in that they have delayed fertilization. They may say good-bye to the males in the Fall, but the females carry the males’ sperm with them as they enter the hibernacula. Atmospheric conditions trigger the fertilization of the egg to ensure the birth of the pups coincide with the emergence of the food source! Amazing!
Formica obscuripes
THATCHING ANTS:
You may have noticed piles of fir needles peppered throughout the forest and at the base of many of the Douglas-fir trees. These are not an abandoned attempt to rake up the forest floor debris but rather are ant colonies! Millions of them! And because they are not equipped to function in cold weather, they are adapted to reduce their body temperature, snuggle up with their favorite 100,000 or so mound-mates, and count sheep until Spring - or in their case, count aphids.
Did-You-Know…
Thatching Ants, also known as Formica Ants, are ranchers? They will keep (or herd) aphids and induce them to produce honeydew as a food source for the colony!
There are hundreds of species of Formica Ants. Some of the more aggressive species have a rather ingenious yet brutal method of taking over colonies of more peaceful natured Formica species. They will send an impregnated queen in the host colony. The hosts may succeed in ousting the queen but will raise the larvae as their own. These larvae, when adults, will then betray said foster parents and kick them out, thus ensuring the colony as their own.
Thatching Ant colonies are polydomous - meaning a colony can consist of several satellite nests. Perhaps the largest known is a supercolony found in the Blue Mountains in Oregon that covers close to 10 acres and includes 210active nests with a population of over 56 million!
As you enjoy Silver Falls and all the beauty it offers, keep an eye out for hibernators emerging in the Spring. Along with bats and ants, Silver Falls is home to other hibernators such as Black Bears, snakes, and ladybugs.