What Time is it in Nature: Insects on Holly

Now is a great time of year for insects at Prairie Ridge!  While you can find hundreds of insect species (probably thousands!) throughout the grounds, you can see a great diversity of insects almost anywhere if you take a moment to look.  For example, one of our holly trees is blooming (the one just inside the entrance) and it is currently covered in tiny nectar-laden flowers:

The flowers may be small, but there are a lot of them and they attract a spectacular variety of insects year after year.  Some things that you’re likely to see on this tree during the bloom are the things you might expect to see, such as bees:

The Honey Bee pictured on the left is not native to the US, but they are important pollinators in our country nonetheless.  You’ll often find dozens buzzing around the holly during the bloom, flitting from flower to flower as they drink their fill of sugary nectar.  The Eastern Carpenter Bees, on the right, have been out and about at Prairie Ridge for over a month now, but they too are happily taking advantage of the holly nectar.  These and other bees are obvious visitors to the tree, making a loud racket and flying around conspicuously as they move from one cluster of flowers to the next.

If you look a little harder, you’ll also find several beetles visiting the flowers:

Ladybugs are well-known as predators, but they do visit flowers from time to time for a sweet treat.  You’ll find dozens of ladybugs lurking among the leaves, including the non-native Seven-spotted Ladybug pictured above.  The beetle in the lower image is a very common visitor to flowers in the summer, a soldier beetle.  They are a little unusual as they do not have the hardened upper pair of wings (the elytra) of most beetles and instead have leathery elytra.  These beetles feed mostly on pollen and nectar, hence they are commonly seen near or on blooming flowers.  You can see lots of them on the holly during the bloom!

Another very important group of insects are often overlooked, the flies:

The iridescent green fly at the top left is a wonderful little fly called a long-legged fly.  Unlike the other flies featured here, they are not nectar or pollen feeders and come to the holly flowers for another reason.  They might be tiny, but these flies are predators and hunt other insects on the leaves near the flowers.  It’s a great strategy to hang out near an attractive food source, and you will often see long-legged flies chewing on aphids, small flies, or other small insects.  The black fly on the lower left is a type of March fly, also known as lovebugs or garden flies.  These flies can form large swarms and are commonly spotted feeding at flowers.  The orange fly on the right is a crane fly, also commonly known as mosquito hawks or daddy longlegs.  These interesting flies are neither a type of mosquito (so they don’t suck blood) nor an eater of mosquitoes, though both urban legends are commonly associated with these flies.  Many crane flies are incapable of feeding at all, and those that do usually eat nectar.  In spite of their large size and their sometimes bright colors, crane flies can be surprisingly difficult to spot in the foliage, so you’ll have to really look to see one.

Bees, beetles, and flies are enormous groups of insects, so it is only natural that they are well represented during the holly bloom.  However, you can find several other groups of insects visiting the tree as well!

Aphids, as pictured on the left, are plant sap feeders.  They jab their long, pointy mouthparts into a leaf vein and suck out the juices.  Their food is very watery and has very few nutrients, so they feed almost constantly and, in some species of plants, can sometimes cause damage when present in large numbers.  The insect on the right might look like a fly, but it belongs to a fascinating group of insects called the scorpionflies.  Male scorpionflies have a bulge at the tip of their abdomen and they hold their abdomens curled up above their bodies, so they really look like scorpions.  However, scorpions cannot fly (thank goodness!), so if you see a scorpion-like tail and wings you are most likely looking at a harmless scorpionfly.  Females, as pictured here, lack the bulbous abdomen tip of the males, but both sexes have an elongated snout.  Scorpionflies feed mostly on dead or dying insects, though they will occasionally sip nectar as well.

Not all visitors to the blooming holly are there simply to feed on plant fluids like nectar or sap.  Some insects and their relatives are there for more sinister purposes:

The jumping spider pictured on the left is a voracious eater of insects!  They’re gorgeous little spiders that use their huge front-facing eyes to search for prey, then pounce.  If you really look, you might see 8 or 10 different species of jumping spider on the blooming holly and, if you’re lucky, you might see one capture an insect for dinner!  The mantid on the right is also a predator and uses its large eyes to find and stalk prey and its large grasping (=raptorial) forelegs to reach out and catch prey.  The mantid in the image here is immature and only an inch long, so it was likely hunting flies, small bees, and other small to medium-sized insect visiting the flowers.  A blooming tree like this is a great place to hang out if you’re a predator.  Insects visiting the holly flowers are often distracted by the sugary food, so it is easy pickings for predators!  You’ll find lots of spiders, mantids, predatory true bugs (such as ambush bugs and assassin bugs), and other arthropod predators lurking near the flowers.

It’s amazing how many different insect species you can find on a single tree at the right time of year.  Next time you visit Prairie Ridge, stop at the holly just inside the entrance fence and take a look.  You might be surprised by the diversity of insects you see!

What Time is it in Nature is a weekly feature highlighting the current plants, animals, and other wildlife at the Musuem’s public outdoor facility, Prairie Ridge Ecostation. Find out more about the natural happenings at Prairie Ridge at our What Time is it in Nature Archive!

(Photos by Chris Goforth)