Ruud Kleinpaste: Recyclers 2 - The famous carpet beetle

Author
Ruud Kleinpaste,
Publish Date
Sat, 24 Jul 2021, 12:15PM
(Photo / Ruud Kleinpaste)
(Photo / Ruud Kleinpaste)

Ruud Kleinpaste: Recyclers 2 - The famous carpet beetle

Author
Ruud Kleinpaste,
Publish Date
Sat, 24 Jul 2021, 12:15PM

A few weeks ago we dealt to the clothes moths and their caterpillars;

The conclusion was that their ecosystem service is to recycle keratin: hair, fur, wool, nails and skin. This is part of the decomposition job that many invertebrates do when an animal dies,

Keratin is really hard to digest; Mammals and Birds can’t do that (cat’s fur-balls; owls ejected pellets, etc); these moths are therefore valued members of the RECYCLING SQUAD.

This appears to be the most common carpet destroyer in Aotearoa; probably because our houses are a lot more “open” than – for instance – in Europe.

Less insulation (especially in older homes), more moisture inside, not well sealed, wooden structures and draughty windows

We also have this habit of living outside a lot: leaving windows and doors open in summer time, so that there is an unlimited indoor-outdoor flow.

D:\My Pics\Invertebrates\Coleoptera\Anthrenus verbasci Carpet Beetle adult GT.jpg

Carpet beetles are quite different from the clothes moths – different family of insects.

Also a different life-cycle and different tactic of chewing on carpet.

The adult beetles (those with the ability to reproduce) have a real beetle “look”… a little bit like miniature ladybird beetles: the membranous flight wings are hidden under some sturdy forewings:

D:\My Pics\Invertebrates\Coleoptera\Anthrenus on marigold polinating PP.jpg

They are actually quite beautiful little beetles: patterned in browny-orange, white and black; a couple of millimetres in size that’s all they are.

But these beetles are not really your problem at all! In fact they are pretty useful pollinators in your garden.

In mid-summer you can find dozens of them in your marigolds, yarrow and even pohutukawa flowers; I bet you that the vast majority of New Zealanders rarely notice them there!

Later in summer when the beetles have mated, they fly into your home through the open door or window and lay their eggs in your woollen carpet.

Little larvae will start gnawing at the keratin (wool), especially on the underside of the carpet backing, so that the woollen strands become loose and are easily sucked up the vacuum cleaner.

D:\My Pics\Invertebrates\Coleoptera\Anthrenus larva on carpet 2 PP.jpg

They look a little like “hairy maggots” and they are pretty resilient down there.

D:\My Pics\Invertebrates\Coleoptera\Anthrenus verbasci larva on carpet sm.jpg

And just like the clothes moths, their habitat of choice is birds nests, lined with feathers and fur, as well as carcasses of dead rodents, hedgehogs and birds

Breaking down the keratin is their gig!

The trick is simple. All you need is a clever enzyme that chops the protein into bits and you will have earned your reputation as one of the few insects that are literally able to split hairs.

Like is the case with clothes moths: control can be achieved with some residual insecticides – active ingredients such as permethrin and other synthetic pyrethroids will do the job well; (Safeworx aerosol cans)

It works well and is residual for 6 to 8 weeks, as long as the substrate treated is not exposed to direct sunlight