by Charlene Simpson
This article is about resident invertebrates at Island Lakes.
Invertebrates are among the oldest known animals on earth dating back 428 million years. They are defined as animals without backbones. Invertebrates range from simple animals found in the ocean to the millions of insects found everywhere in the world (Fun Facts about Arthropods).
Butterflies – Look for butterflies in summer. They can be found on flowers, drinking water from mud, or resting on bare places. These gorgeous creatures that brighten our landscapes have transitioned from egg to caterpillar to pupa and emerged as adults. Metamorphosis is synchronized with the seasons of the year (Neill, 2001). It is the adults that caption our attention.
Most of the butterflies we see at Island Lakes are year around residents. They survive the winter by shutting down metabolism to the bare minimum – the equivalent of hibernation.
Dragonflies – During the warmest days of summer dragonflies can be seen in the air space over our lakes. They are strong fliers, zipping and chasing, all the while putting on an acrobatic air show. When they come to rest on nearby vegetation they afford a photo opportunity. As with butterflies, dragonflies transition through life stages: egg to nymph to adult.
I took these pictures this 4th of July weekend at the margins of the small lakes along Lake Isle Drive.
Praying mantis – The praying mantis is named for the kneeling position of its front legs which suggests the position of prayer. But far from praying for forgiveness she is likely praying for her next meal. The praying mantis has a triangular head that can swivel 180° which makes it a formidable predator. A notorious mating behavior of the adult female is eating her mate just after – or even during – mating (National Geographic website). The eggs she lays must be nourished.
Open your eyes to the natural world
that is our heritage at Island Lakes!
- Fun Facts about Arthropods
- Gordon, Steve and Cary Kerst. 2005. Dragonflies & Damselflies of the Willamette Valley, Oregon: A Beginner’s Guide. CraneDance Publications. Eugene, OR.
- National Geographic
- Neill, William. 2001. The Guide to Butterflies of Oregon and Washington. Westcliffe Publishers. Englewood, CO.