The last of the Butterflies for 2017

A Common Buckeye Butterfly. The eyespots may be used to scare away predators.

Written by Joe Reynolds
​New York Harbor Nature Blog

​Warmer than usual temperatures during the last half of October and early November brought out unexpected hues of color around New York Harbor. Hoards of butterflies have been fluttering along the edge of the estuary making their way to winter homes.
 
Unseasonably warm temperatures last weekend brought out large populations of Common Buckeye butterflies (Junonia coenia), cloudless sulphur butteflies (Phoebis sennae), and even a few hardy monarch butterflies (Danaus plexippus). All were enjoying the sweet nectar of many asters still in bloom along the edge of a relic maritime forest at Sandy Hook National Recreation Area in New Jersey, located at the mouth of New York Harbor. 

​While many people know that monarch butterflies migrate thousands of miles to the mountains of Central Mexico to overwinter, they are not the only butterflies to wander long distances.  The Common buckeye butterfly cannot survive cold winters and freezing temperatures around New York harbor, so they migrate south each autumn. The buckeyes often fly south to overwinter in Gulf Coast states like Florida. The buckeyes prefer to migrate along the coast in open areas where the warmth of sun keeps their bodies heated, and important task for a cold-blooded or ectothermic animal, which means an animal’s body temperature is dependent on the outside environment for heat.
 
Come spring, adult buckeyes fly north to reproduce. The first brood travels in late spring and summer to colonize most of the United States and parts of southern Canada. 

​The cloudless sulphur is one of New York Harbor’s most common butterflies. It tends to be most seen during its fall southward migration along the coast. The butterfly tends to travel long distances along dunes and forest edges as it travels southward to states in southeastern United States.
 
Butterflies are on the move, but not for long. A strong cold front this weekend will likely squash most colorful butterfly activity around New York Harbor until next spring. Enjoy it while you can.