Losing Ladybugs

(Note: this post has been revised to clarify that the convergent lady beetle is native in North America – though it is being moved around as a pest control agent, including into parts of South America, where it isn’t native.)

I saw two native ladybugs this week at our Platte River Prairies, which shouldn’t be as notable as it is. Unfortunately, over the last 20 years, native ladybug populations have steeply declined – especially among some species, which are almost never seen anymore in many places. During the same time, non-native ladybugs (lady beetles) have dramatically increased in abundance. As a result, the vast majority of lady bugs I see are non-native (particularly the 7-spotted and Asian lady beetles). Finding a native species is a cause for celebration.

This little beauty I found at the Platte River Prairies this week is Hippodamia parenthesis – the Parenthesis Lady Beetle. It is a native species here and smaller than the three big non-native ladybugs.
This was taken with my phone and cropped liberally. It’s not a great photo, but I’m pretty sure it is Brachiacantha ursina – the Ursine Spurleg Lady Beetle. Ladybugs come in a fairly wide range of sizes and color patterns. If you’re only looking for red/orange bugs with a few black spots, you’re likely overlooking a lot of others (especially the native species).

Frequent readers of this blog will know that competition from honey bees (non-native species) has contributed to the decline of native bees in North America. There are many other factors, though, linked to those bee declines and it’s hard to know exactly how important honey bee competition is. A similar problem exists with investigations into disappearing ladybugs. There are certainly strong correlations between increases in non-native ladybug abundance and decreases in native species populations. However, habitat loss and degradation, pesticide use, and many other factors are at play as well.

Scientists continue to delve into this and there are opportunities for you to help. For example, the Lost Ladybug Project is a community science effort that encourages people to send in photos of both native and non-native ladybugs to build understanding about changes in populations. Their website has information about how to become involved, but also some great information on how to identify ladybug species. For people in the Great plains, a particularly nice resource linked to on that site is the Ladybugs of South Dakota poster, which has terrific photos of 80 ladybug species. I’ve found it to be an easy and very helpful tool to identify species.

The Convergent Lady Beetle (note the two converging white lines) is native in North America and often sold for pest control (including in places where it isn’t native, which is scary).
The non-native seven-spotted ladybug, which has three spots on each of its elytra (its 2 hard wing coverings) and one spot split between them.
The non-native Asian (aka Harlequin) Lady Beetle might be the most conspicuous of the invasives because it often congregates in large numbers around human dwellings. It can have a wide range of colors and spot patterns but usually has a ‘W’ shape on its pronotum (the plate between the head and wings).

Ladybugs are an easy group of insects to learn because their spot patterns make them relatively easy to identify (though some of the species – especially the Asian lady beetles – can be variable in appearance.) Whether or not you join in community science efforts related to ladybugs, it’s important to be aware of what species you see around you. The two photos above show the most common non-native ladybugs seen around Nebraska. If you see something that looks like a ladybug and it doesn’t look like one of those two, take note. Even better, take a picture!

Once you have a decent photo, you’ll have a good chance of identifying the species. If you can’t figure it out, you can submit it to iNaturalist, Bugguide, or other sources. Pretty soon, you’ll become familiar with what the non-natives look like. The bad news there is that you’ll probably start to realize how dominant they’ve become in your area. The good news is that when you actually find a native species you’ll know it’s time to celebrate!

As I was looking through my ladybug photos for this blog post, I came across this image from The Nature Conservancy’s Flat Ranch in Idaho. I’m pretty sure it is the Transverse Ladybug (Coccinella
transversoguttata richardsoni), which is listed as ‘Lost’ on the South Dakota poster I mentioned above. As soon as I finish this post, I’m going to submit the photo to the Lost Ladybug Project. Then I’m going to celebrate!

Photos of the Week – June 17, 2021

l’ve been in the field a lot over the last week or so. It’s been very hot, so I’ve been trying to get outside by sunrise. That’s been helpful in terms of getting work done in reasonable temperatures, but also means I’ve had some good photography light. I have hundreds of photos from the last 8 days, but among the subjects I’ve photographed, spiders have been prominent.

Below is a selection of spider photos from the last week or so. Many of you know my proclivity for photographing crab spiders, and several of those are included, but there is a nice selection of others as well. Enjoy!

Crab spider on a wilting shell leaf penstemon flower. Nikon 105mm macro lens. ISO 400, f/11 at 1/160 sec.
Tiny spider and orb web. Nikon 105mm macro lens. ISO 400, f/11 at 1/500 sec.
Long-jawed orbweaver, backlit on yarrow. Nikon 105mm macro lens. ISO 400, f/13 at 1/80 sec.
I think this crab spider had just finished feeding on this stink bug because it dropped it shortly after I took this photo. Nikon 105mm macro lens. ISO 400, f/11 at 1/160 sec.
Crab spider silhouette. Nikon 105mm macro lens. ISO 640, f/18 at 1/160 sec.
Tiny spider in its web on a shell leaf penstemon plant. Nikon 105mm macro lens. ISO 500, f/14 at 1/200 sec.
Spider hiding on a stem of needle-and-thread grass (Tibellus sp?). Nikon 105mm macro lens. ISO 320, f/11 at 1/250 sec.
Lynx spider on showy milkweed leaf. Nikon 105mm macro lens. ISO 500, f/16 at 1/250 sec.