Pond Life, Part 5 - Insectivores

In the vast web of life insects form one of the food links between plants, the original source of nutrition, and the animal kingdom. Animals that rely on eating them are called insectivores.

A Common Yellowthroat hunting insects on a water lily pad

I sought out naturalist Barbara Buls Boudreau for her perspective on the place of insects in the scheme of things. Having lived extensively in Japan and Zaire, as well as various parts of the United States, she exudes a global ecology. "One of the things I've always felt is that I would never want to live somewhere where there were no insects, because insects are the building blocks of our entire existence. That's where it starts, in the balance of our larger world."

Barbara Buls Boudreau

Regional Interpretive Coordinator

MA Department of Conservation and Recreation

"One of my goals is that people will see the world as their home, to feel as comfortable outside and as understanding of what's around them as they do when they're inside their house."

Fish eyeing the pond surface for insects, from below

An agile Eastern Phoebe, in the Flycatcher family,

plucking insects at the water surface, from above

Eastern Kingbird, another Flycatcher,

on the lookout for insects from its pond-side  hunting perch

Barn Swallow hunts insects over the Halibut Point quarry...

...and feeds its young on the quarry rim.

Many insects are predators of other insects. Among the most voracious are dragonflies with remarkable vision and flight dexterity.

A Green Darner dragonfly patrolling a pond surface

Barbara particularly admires these winged warriors. "They're like birds of prey. They will find a station, a place to perch, a lot like raptors do from specific branches where they hunt."

"One of the things you find in pond muck is dragonfly larvae. They look like aliens. They're voracious, and they feed on other things. They even catch small fish. You have to be careful with them as juveniles, because they will bite, and it hurts a lot. When they're ready, they crawl out on some sort of stem, crack out of their shell, and become these amazing dragonflies. They're like B-52 bombers."

Familiar Bluet damselfly

"On the microscopic level, they live in a very violent world. A lot of nature is very violent. But dragonflies are one of the coolest things there are, because there are so many different kinds of them, and they come in so many colors. You think of nature as green and brown, but they come in Crayola-neon colors."

A female Cardinal captures a dragonfly at the edge of the quarry.

Of course dragonflies fall prey to other creatures around the pond, including frogs, if they can catch them. A normally seed-eating Cardinal seeks out animal protein to give to its developing young, which become gradually vegetarian.

Spider trapping a damselfly

Another insectivore catching Barbara's admiration is the spider. "A spider is an animal that actually has a plan. It's incredibly industrious. It attaches a silk thread to something, swings back and forth to another anchoring place, and weaves a whole web. It knows where it can walk, and where it can't. The silk spun from within its body is one of the strongest elements in nature, yet so thin and almost invisible."

Brown Bat over a pond at Halibut Point

"Some of the most beneficial wildlife to people are the most maligned. Like spiders and snakes, bats are one of those creatures people are afraid of. They think bats are creepy and carry rabies and get caught in your hair. Even if you mention them they kind of shudder. Yet they are so beneficial to us, living on mosquitoes and other insects. They're not at all aggressive.

"They're unique, navigating by echo-location to catch things in total darkness. They scoop a bug into a pouch of skin called the uropatagium, between their back legs and their tail. Then they fold down to snatch it into their mouth so they can eat while they fly. They do that with their catcher's mitt.

"A bat is a mammal that can fly. Over evolutionary time it figured out a way to fly. Its wings are skin rather than feathers. Its skeleton looks just like a person with really long fingers. Look at the wing frame in the picture. Just above the head is its upper arm, then it turns left, and that's its lower arm. The thing that sticks out in front of the wing is its thumb. Those long bones that support the wing are fingers. It pursues insects in their own element."

Eastern Amberwing dragonfly

"One thing I really love to do with kids is show them things under a microscope. An insect is perfect for that, because they're so Sci-Fi. It's like things that they see on a movie screen. I love the way, when you show people part of anything‒it can be part of a leaf or part of a stick, or your finger, or anything‒under a microscope. Ninety-nine per cent of people go, Wow! That's what you want. You realize when you look close how fantastic it is. It's the sense of wonder. Sometimes all it needs to be is pointed out to us."