Brown ground beetle migration

Southern California inland location, mostly dry hot summers (this year extremely hot), mild winters -- although some years a few days under 32 degrees. I've lived here for fifteen years and have never seen what I am calling, after a little research, a brown ground beetle. Three days ago, a neighbor across the street mentioned the beetles crawling up the side of her shed. Then, she noticed them crawling up the back side of her mobile. Yesterday, she mentioned using three cans of bug spray. Yesterday, I checked, and there were only a few climbing up the side of my house. Today, the beetles were crossing the street in fairly large numbers and many were climbing up the mobile front, sides, and back. The same thing is occurring in other locations in the neighborhood. The only unusual event in the neighborhood has been a switch from manually read electric meters to signal read electric meters last week and gas meters about two months ago. The process for new electric and gas meters took eight months, streets dug up, and new meters place in front of mobiles instead of at the rear.

Question: Is it usual for brown ground beetles to migrate in the fall? Could the new electric meter signals be the cause? I can understand the beetles wanting to find a warm location for the winter. However, it is a little strange to see this type of migration for the first time after living here for fifteen years. Also, I have an indoor/outdoor cat and don't like to use harmful chemicals. Any suggestions?

Contributed by MargaretM on 27 September, 2017 - 10:10pm

A picture would help

Without an image we can only guess. Perhaps it isn't even a beetle but a stink bug. Many people mistake them. It could be the invasive marmorated stink bug. It was first seen around twenty years ago. Its range and populations have been growing at a fast pace in recent years.

… Beatriz Moisset, 29 September, 2017 - 1:52pm

Brown ground beetles?

Sorry, at this time I don't have access to a camera with a closeup lens or a cell phone. I did recheck this site and found four photos of a leaf beetle. The photos highly resemble the beetles being discussed. There were, however, no dimensions listed. The beetles, arriving on foot and climbing walls, are 1/4 inch long.

After writing the above, I talked with two neighbors who had the outside of their homes sprayed by Corky's last night and today. Both neighbors were told: boxelder bug. I'm just going to accept boxelder even though I could see no red markings.

Arthropods (Arthropoda) » Hexapods (Hexapoda) » Insects (Insecta) » Beetles (Coleoptera) » Water, Rove, Scarab, Long-horned, Leaf and Snout Beetles (Polyphaga) » Series Cucujiformia » Long-horned and Leaf Beetles (Chrysomeloidea) » Leaf Beetles (Chrysomelidae) » Eumolpinae » Eumolpini » Section Iphimeites » Brachypnoea

… MargaretM, 29 September, 2017 - 7:10pm

Suggestions

Hi,

Don't want to come off as too critical here, but here are my suggestions. These suggestions will help nature and the planet as a whole.

1) Make your cat an indoor only cat - this would protect your cat from your neighbor's indiscriminate use of poisons and also protect birds and other wildlife from your cat.
2) Please try to convince your neighbor(s) not to spread poisons around so much. It's bad for the planet.
3) If anything gets in your house just safely capture it with a cup and usher it outside. Be very careful to avoid being bitten/stung.

… Jeff Gruber, 28 September, 2017 - 12:18pm

Brown ground beetles

Thanks for your suggestions sent with wisdom, knowledge, and heart.

1. Regarding the cat. Without going into too much detail, it is too late to to change letting Cooper, fifteen years old, out for what has become only an evening stroll. However, I do understand your concern for protecting wildlife. There have been times when I felt sad while at the same time thinking the freedom of being outside was important, especially for a cat born outside to a mother who was surviving by hunting after being shot with buckshot.
2. I believe my neighbor understands my concerns about using toxic sprays outside. However, via another neighbor, I heard a professional has been called to spray outside. I will check and keep the cat in when this occurs. Fortunately, I live in a part that doesn't even use weed killer.
3. Some beetles did arrive in the house. There were too many and not conveniently located to use your capture and release method. I have used your method in the past to transport spiders outside, and once while living out in the woods, to escort a tarantula that was living outside the house to a new location two blocks down a dirt road.

Thanks again for your suggestions. The Earth is going through a perilous time.

… MargaretM, 28 September, 2017 - 8:07pm

Please submit a good overhead photo or two

of this insect under the ID Request section. Along with your new photos you might insert comments that briefly refer or link to your post here under General Discussion. I'm not sure if your use of the term "ground beetle" is the taxonomic one (family Carabidae) or simply a descriptive one (an insect/beetle that crawls on the ground could represent many different families). At any rate, true ground beetles (Carabidae) don't "migrate", but common species may give that impression by emerging from larvae in large numbers in the fall.

… Peter W. Messer, 28 September, 2017 - 8:25am

Brown ground beetles?

I want to apologize for the somewhat stupid salmon comment. In addition, I returned to BugGuide, because there was another post that suggested photos. I decided to recheck for photos on BugGuide that might match what I am calling brown ground beetle, and found photos of a leaf beetle that highly resembles the beetles in question. No size was mentioned. Again the arrivals are about 1/4th inch in length. Would this still fit in with "...emerging from larvae in large numbers in the fall."? Whatever these critters are, I am trying to fend them off with the hose's jet spray outside and squashing the few that manage to enter the house.

After writing the above, I talked with two neighbors who had the outside of their homes sprayed by Corky's last night and today. Both neighbors were told: boxelder bug. I'm just going to accept boxelder even though I could see no red markings.

Arthropods (Arthropoda) » Hexapods (Hexapoda) » Insects (Insecta) » Beetles (Coleoptera) » Water, Rove, Scarab, Long-horned, Leaf and Snout Beetles (Polyphaga) » Series Cucujiformia » Long-horned and Leaf Beetles (Chrysomeloidea) » Leaf Beetles (Chrysomelidae) » Eumolpinae » Eumolpini » Section Iphimeites » Brachypnoea

… MargaretM, 29 September, 2017 - 7:50pm

Brown ground beetles

Thank you for your response.

I wish I could supply a photo, but I can't. What I am describing as a brown ground beetle is dark brown, about 1/4th inch long, and looks like a bug on the Clickable Guide to the left of the screen -- far left on the third line from the bottom.

The last sentence of your response seems to be an accurate description of what is occurring: "....but common species may give that impression (migration) by emerging from larvae in large numbers in the fall. All I can say is that if the larvae turned into salmon, no one in the neighborhood would be complaining.

Just wish someone had a nontoxic solution to the house invasion.

… MargaretM, 28 September, 2017 - 8:27pm

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