Those Other Flower Visitors

If you look closely at wildflowers, you’ll often see insects moving around and between them. Many of those insects, of course, are bees, flies, butterflies, moths or other pollinators. While these small creatures are eating resources created by the plants they visit, they also provide services in return. The insects get pollen and/or nectar to feed themselves or their babies but also (unintentionally) facilitate the fertilization of ovaries that allow plants to produce seeds. It’s a pretty good trade all around – though with lots of variation in terms of how much each side benefits from the other.

All of that makes a pretty good story of cooperation among the earth’s creatures, but the full picture is much more complex. A strong percentage of insects hanging around flowers provide no benefits to the plants, and many do considerable damage instead. For today, I’ll ignore the predators who use flowers as hunting grounds, even though they are infinitely fascinating. Instead, I want to feature a few examples of ‘freeloading’ insects who take and take from flowers, but never give anything back. …Or at least don’t give back to the flowers.

Leaf beetles feeding on aromatic aster (Aster oblongifolius). Nikon 105mm macro lens. ISO 500, f/14, 1/320 sec.
A longhorn beetle on upright yellow coneflower (Ratibida columnifera) with its face full of pollen after eating. Nikon 105mm macro lens. ISO 125, f/20, 1/80 sec.

Numerous beetle species feed on flowers, eating pollen and nectar, but also petals, anthers, and other vital anatomical features. Some of these beetles can provide pollination services if they move between blossoms, but that benefit can often be outweighed by the destruction they create. Depending upon the number of beetles working over a flower, that level of destruction can be minor or catastrophic for a particular plant.

That doesn’t make these beetles evil or deserving of our dislike, however. Beetles have a right to make a living too, and there are plenty of flowers for everyone in a prairie (or even a garden) that’s well-managed. In fact, as I argued in a recent post, providing flowers to feed beetles and many other creatures should be part of our role as gardeners and land managers. Beetles play all kinds of vital roles in ecosystems, so keeping them around is certainly a good thing (excepting invasive species like Japanese beetles, of course, which can create far more devastation then benefits.)

Oil beetle on pasque flower (Pulsatilla patens) at the Niobrara Valley Preserve. Nikon 105mm macro lens. ISO 400, f/20, 1/640 sec.
Weevils on Platte thistle (Cirsium plattensis) at the Niobrara Valley Preserve. Nikon 105mm macro lens. ISO 320, f/14, 1/125 sec.
Grasshopper on plains sunflower (Helianthus petiolaris) at the Niobrara Valley Preserve. Nikon 105mm macro lens. ISO 400, f/14, 1/160 sec.

Grasshoppers, katydids, and crickets represent another group of insects that are often found chomping on flowers. These little scamps feed on multiple parts of the flowers, but they probably provide even less accidental pollination than beetles do. However, like beetles, this group of long-legged buggers is really good to have around. If nothing else, they are a major food source for birds and many other small predators (and there’s much more to them than just that but that’s another post). Instead of getting mad at grasshoppers for eating flowers, we should be expressing gratitude to plants for creating enough flowers to support grasshopper populations!

Tree cricket on tall thistle (Cirsium altissimum). Platte River Prairies. Nikon 105mm macro lens. ISO 640, f/18, 1/80 sec.

Caterpillars and similar-looking larvae of flies, beetles, and other insects are also commonly-found feeding on flowers. As with beetles and grasshoppers, the result can be pretty negative for individual flowers, but – again – the sacrifices made by those plants help support the broader ecosystem. Caterpillars are another huge food source for other animals and the vast majority end up as food rather than moths, butterflies, or other adult insects. They might as well enjoy a good meal while they can, right? I’ll also admit my personal bias here, since my favorite insect in the world is a little flower-eating caterpillar.

Annual sunflower (Helianthus annuus) being eaten by caterpillars of several larval stages. Nikon 105mm macro lens. ISO 640, f/13, 1/640 sec.
Giant robber fly (Promachus vertebratus) laying eggs on stiff sunflower (Helianthus pauciflorus). Nikon 105mm macro lens. ISO 500, f/10, 1/250 sec.

Sometimes, the way insects utilize flowers is less obvious than a big ol’ caterpillar chewing on the anthers and pollen of a sunflower. Loads of insects use flowers as a place to lay eggs, many of which hatch out and then feed on the flower – often hidden from our view. Others, like the giant robber fly pictured above, apparently lay eggs in flowers only so their larvae can drop off and burrow into the soil to chase down beetle larvae (thanks beetles!). So why do they lay their eggs in flowers and not in the soil? I have no idea.

More commonly, insects laying their eggs in flowers because that flower will provide both their home and their food source once they hatch. Some of those larvae eat parts of the flower itself, but many feed on the developing seeds, taking advantage of those highly concentrated packets of nutrition. If you peel open the head of a thistle or sunflower after it has stopped actively blooming, you’ll often find a few tiny ‘grubs’ chewing on the seeds within.

Once again, you could denigrate those larvae and their parents as pests if you like, but you’d be missing the larger picture. Those blossom-chompers and seed-munchers are part of the incredibly complex and interconnected web of prairie life. The give-and-take relationships between flowers and insects have existed for millennia and will continue for many more. This spring and summer, as you wander prairies, gardens, and other places where flowers bloom, consider paying a little extra attention to who else is enjoying those same blossoms. Those other visitors will undoubtedly have stories worth learning.

Fruit fly on tall thistle (Cirsium altissimum), probably scouting for a good place to lay her eggs. Nikon 105mm macro lens. ISO 640, f/16, 1/400 sec.

Photos of the Week – May 6, 2022

Today’s post includes a raft of photos I’ve taken over the last month that didn’t really fit into the themes of other posts. I’ll include commentary with some and not with others. Enjoy!

Robust camel cricket (Udeopsylla robusta) at The Nature Conservancy’s Platte River Prairies. Nikon 105mm macro lens. ISO 640, f/18, 1/400 sec.

These first two photos are from the Platte River Prairies. We came across the cricket (above) during some plant identification practice with the Hubbard Fellows. It’s the first time I’ve noticed a camel cricket along the Platte, but I’m sure they’re common. This one happened to be in the middle of a large patch of open sand on a cold and windy day, so it was easier to see.

I like the photo of sand dropseed (below) because it highlights the ‘flags’ I point out to people as an easy way to identify this species from a distance. After sand dropseed blooms, it wraps its flower in a long papery sheath while its seeds develop. When we harvest seeds of this species for our restoration work, we’re basically clipping long tubes off the tops of the grasses, within which are thousands of tiny seeds. As autumn progresses, the sheaths (those we don’t harvest) open up and drop their seeds. The remains of those sheaths then flutter in the wind all winter and spring, making the species stand out among others.

Banners of last year’s sand dropseed plants (Sporobolus cryptandrus) at The Nature Conservancy’s Platte River Prairies. Nikon 105mm macro lens. ISO 320, f/6.3, 1/640 sec.
Grasshopper nymph with tiny ant attached to its foot. Gjerloff Prairie (Prairie Plains Resource Institute). Nikon 105mm macro lens with Raynox dcr-250 macro attachment. ISO 320, f/20, 1/250 sec.

Last week, I shared some wildlife photos, including some from Gjerloff Prairie. Here (above and below) are two I didn’t include. The grasshopper nymph above was feeding on prairie dandelion (Nothocalais cuspidata) when I spotted it. As I photographed it, I noticed something sticking to its front foot but didn’t think much about it. Later, when looking through images on my computer, I realized it was an ant! It appears dead and I don’t really have an explanation for why it’s there. The wildflower below is (I think) Platte milkvetch, a charming little plant that grows on the tops of dry loess ridges at Gjerloff Prairie.

Platte milkvetch (Astragalus plattensis). Gjerloff Prairie (Prairie Plains Resource Institute). Nikon 10.5mm fisheye lens. ISO 320, f/22, 1/160 sec.

These next four photos were taken last weekend in the Flint Hills of Kansas. My wife, Kim, was running in a 50 mile race on Saturday and I was, once again, her crew. 50 miles of running, especially when a 35 mile wind is in your face during the second half, takes up most of a day, so I had plenty of time to wander around the landscape on my own. Since it’s a mostly privately-owned landscape, I stayed on or near the road, but still managed to capture a few images that depict the prairie.

Steer in burned prairie – Kansas Flint Hills prairie. Sigma 100-400mm lens @195mm. ISO 500, f/9, 1/320 sec.
Scissor-tailed flycatcher in the Kansas Flint Hills. Sigma 100-400mm lens @400mm. ISO 640, f/6.3, 1/600 sec.

If you’re familiar with the Flint Hills, you may know that a common ranching strategy is something called ‘early double stocking’. The system involves a spring burn and then grazing with yearling cattle for the first half or so of the growing season. Animals are then pulled off in time for grasses to grow back during the late summer and fall so the site can be burned again the following spring. Cattle gain a lot of weight during a short period because of the highly nutritious grass production following a burn.

The early double stocking system seems to work well for ranchers in terms of livestock production and it also helps protect against brush encroachment, which is a major threat in the region. Unfortunately, if too many ranchers use the same strategy, it doesn’t leave much unburned habitat for wildlife that need that, and any species vulnerable to April fires are affected across huge swaths of the landscape. It’s impressive to see the pro-prescribed fire culture in the Flint Hills, but from a conservation standpoint, I’m glad there seems to be a gradual shift toward a little more heterogeneity the application of fire.

Cattle grazing Flint Hills Prairie in Kansas. Sigma 100-400mm lens @100mm. ISO 640, f/5.6, 1/2500 sec.
Ornate box turtle on a gravel road in the Kansas Flint Hills. Nikon 105mm macro lens. ISO 320, f/20, 1/250 sec.

The last two photos (below) are show a western meadowlark that was singing right outside my viewing blind at the Niobrara Valley Preserve in mid-April when I was photographing sharp-tailed grouse. As with the grasshopper photo earlier, it wasn’t until I got home and looked at images on a large screen that I noticed something about the meadowlark’s feet. In some photos, it was perched on both feet, but in many, it was standing on only its left foot and seemed to have its right tucked up against its body.

This is interesting for a couple reasons. I assume it was doing this as a way to keep its right foot warm on a cold and windy morning. Maybe it rotated which foot it held against its warm body and I just happened to photograph it only when it was hiding its right? Or maybe only its right foot was particularly cold. More fascinating to me is its ability to balance on one foot on a branch while singing on a windy morning. It seemed effortless – the bird certainly wasn’t wobbling around. I know birds don’t weigh much, but I was still impressed.

Western meadowlark. The Nature Conservancy’s Niobrara Valley Preserve. Sigma 100-400mm lens @400mm. ISO 800, f/6.3, 1/800 sec.

It was a rainy week across much of Nebraska this week, bringing much needed relief from the drought conditions across most of the state. Even the three inches we got didn’t come anywhere close to ending those drought conditions, but it sure made everyone feel better. It’ll also be great for the wildflowers blooming during the next few weeks – and all the bees and other insects who rely on them.