From what I’ve observed over time, most living creatures out there have an inbuilt behavioural pattern to follow regular food availability to its source.
It looks to be essentially an instinct generated through competition – i.e. making sure a given animal is first in the queue and ahead of his/her peers.
You can see this for yourself when feeding ducks – as you continue to throw chunks of bread into the water, not only do the numbers of ducks increase but they gradually get closer and closer to you in order to grab the bread the minute it leaves your hand.
The same is true for dogs and cats – start flipping treats out one by one and you’ll observe the same response where they eventually get as close to your treat issuing hand as possible and watch its every move with an unshakeable stare.
For the fisherman out there that spend time waist deep in a flowing river trotting down with a float, a shoal of fish will do the same with the loose feed you are throwing in – provided they don’t get spooked they will slowly work their way up until literally under the rod tip to catch the feed as it hits the water.
We humans are civilised and have evolved beyond these crude primal instincts right? We politely queue surely?
Not when its about money we don’t! You have to take a commercial view when looking at humans but we too do the same when money is what we are chasing.
Best example I think of to illustrate this is what I observed going on in Cornish harbours.
Fisherman go out in yellow smocks and catch baskets and baskets of whelks, clams, shellfish and fishfish from somewhere out in the deep.
This all ends up in shops up and down the country to be sold to us on the High Street at sky high prices.
There is a middle man chain in between us and the fisherman – wholesalers, brokers etc.
Each link of the chain puts a mark up on the cost and the amount of mark up applied in turn depends on how good (i.e. how fresh/how big) and how many of the produce is involved.
So very much in the interest for the first step of the middle man chain – i.e. the guys buying the stuff from the fisherman – to form strong relationships with the best & busiest fishermen.
And how do they do this?
Well as the fisherman dock their boats and climb the steel ladders that bring them up to dockside, these guys are standing at the top of the ladders waiting!
The deal is done and cash parted then and there.
They’ve learnt to go right to the source of the income and be there ready and waiting less their competitors do this whilst they are waiting in the harbour car park!
The same is very much true for rats
Essentially a waste system is like a river and any food items that get washed down your sink or go through the dishwasher all end up flowing along the pipework in a stream.
Rats will follow this food stream like Hansel & Gretal followed the breadcrumbs for the reasons outline above.
Eventually they will journey up your private drainage and look to collect the food from the point where it exits the sink or washing machine outlet (so as to be at the ‘top of the ladder’).
Problem is, this encourages the rats to occupy and exploit your private waste system pipework and if there is a redundant inlet or vulnerable piece of PVC pipework/connection then these rats will find it and create a link between waste system and building fabric.
In the case of modern PVC pipework, they even make that link themselves by gnawing through it!
So key is to try and minimise the amount of food being introduced into your waste stream – scrape plates into the bin (not the sink), don’t pour grease & fats down the plughole and avoid sink macerators like the plague.