Feature articles

15 May 2020

Pest breeding cycles: counting the pests thriving in your business during lockdown

When many hospitality and retail businesses were forced to close several weeks ago, some chose not to continue with routine pest management contracts during the lockdown.

BPCA warned this wouldn't work and that pest populations would thrive if left unchecked. This has been the case and we're now seeing many closed businesses getting back in touch with members.

What do we mean, when we say they'll thrive? We're here to give you a little bit of context, to show you how one pair of breeding pests can become a substantial infestation in a short space of time. 

221 pestaware-pest-breeding-cycles-and-protecting-your-business

Rat breeding cycles

First, let's take a look at rats.

One breeding pair of rats (male and female) usually have around eight kittens in a litter on average. They could have two litters in two months, so 16 kittens if environmental conditions are favourable.

These young take a good 9-12 weeks to become sexually mature, so an initial infestation will take a little longer to establish but, once those young are sexually mature, the population will grow quickly.

Within a year you're looking at approximately 1,250 rats, in and around your business, ruining stock, contaminating food and putting your staff and clients at risk.

Mice breeding cycles

Moving on to the other most popular rodent pest species, one breeding pair of mice could have two litters in two months.

On average, there are usually six pups in the litter, so 12 young in two months with the original breeding pair.

Those first six young will take a while to become sexually mature, maybe six weeks. They could all then have a litter themselves, then the numbers really start racking up!

One female can have five to ten litters per year. 

By the end of a year, you can easily end up with 2,000 mice, all scurrying around carrying dirt and bacteria with them, transferring it to your counter tops, cabinets, pantry and anywhere else they travel.

Life cycle

Cockroach breeding cycles

Over to insect species, and one female cockoach with a fertilised ootheca (depending on the species but let's go with the most common, German cockroach) could carry two egg ootheca in two months, each containing around 30 nymphs.

That's 60 ‘young’ in two months. These young will take minimum of three months to get to breeding capability, so shouldn’t go much further than that with just one female.

Obviously, that is rarely the case. An established population with around 10 fertile females could produce 600 nymphs in two months.

If clients and customers spot evidence of cockroach infestation in the premises you manage, they are likely to complain and request a refund.

They'll report on your company negatively, potentially resulting in closure by an Environmental Health officer and making it unlikely for some people to want to do business with you again.

Fly breeding cycles

This is trickier, as there are so many species, but the Common housefly can lay up to 150 eggs on rotting vegetable matter or animal faeces.

She may do this five times throughout her one month life span. 

It takes no more than a month for them to become adult flies, so in two months you're looking at 750 flies.

It is likely the numbers will fluctuate, as flies come and go, not like the previous pest species we've mentioned, which tend to stay in the areas they breed in. 

WORRIED ABOUT PESTS?

If you run a business and you're concerned about pest infestations, use our online tool to find a BPCA member company to help.

Find a pest controller

Source: Online

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