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The direct poisoning of the sewers in the Borough with fluoracetamide referred to
in my last report has continued throughout 1969. As in 1968 four treatments were
given to the Richmond/Barnes sector and two to the Twickenham sector. The effect
of this treatment throughout the Borough was checked in the latter part of the year
with a 10% test treating programme. The low take obtained in the 1968 tests in the
Twickenham area has been maintained, only 8 out of 266 manholes — 3% — showing
bait take. In the Richmond/Barnes sector, which in 1968 had shown a 21.2% take of
manholes tested (44 out of 207), this year revealed a most marked reduction to 2.4%
(5 takes in 205 manholes tested).
These results indicate that the sewers in the two sectors of the Borough now
appear to have much the same level of rat infestation. It may not be possible to reach a
completely 100% rat-free sewer system but it would seem reasonable to take the view
that something very close to this figure is now attainable in the near future.
Domestic premises, particularly back gardens remain the most commonly rat
infested places. Residents would assist in reducing the prevalence of the rodents if
they were to give special attention to the following points :
(a) Garden sheds, especially those with wooden floors provide a harbourage in
the under floor space.
(b) Outdoor pet or poultry hutches are vulnerable places especially because of
scattered grains or other food which attract the rats.
(c) Rubbish heaps, rockeries and so-called compost heaps are frequently found
to harbour rats. A heap of rotting garden waste is not necessarily a compost
heap. Properly made compost heaps should be too hot internally for rats
but a rough heap of grass mowings, etc., is often an attractive breeding area.
(d) The misguided feeding of birds by throwing out of waste food, stale bread,
etc., attracts not only rats but sometimes squirrels and pigeons.
On more than one occasion it has been found that rats are using the underground
pipes carrying the Post Office telephone cables. In only one instance was there clear
damage to installations, but the rats bad evidently found in the system a ready-made
underground communications network and, once gaining access, made full use of it for
movement. With the assistance of the Post Office staff poison bait was laid in junction
boxes under the pavements and this apparently dealt with the infestation. Some reconstruction
of defective boxes by the Post Office reduced the likelihood of their future
use by the rats.
Satisfactory communications have been established with British Rail to obtain
treatment by their Contractors of sections of permanent way embankments within the
Borough where we had pinpointed sources of rat infestations of adjoining properties.
At a number of points these embankments have clearly provided protected harbourage
secure from public access from which the rats have raided premises whose boundaries
adjoin the line of rail. In the majority of cases action by the British Rail's Contractor
and our own efforts succeeded in clearing up the trouble.
An alert Rodent Operator carrying out contract rodent control work in a factory
in Richmond noticed extensive droppings which in form and size were not typical of
those of the common rat. Our examination of specimens and a check by the Infestation
Control Division of the Ministry of Agriculture, Fisheries and Food confirmed the likelihood
of them arising from an infestation by the black or ship rat. Subsequently a
dead body made certain of this identification. It was interesting to speculate how ship
rats, normally confined to port areas, came to be found in Richmond. The work in the
factory involved the assembly and repair of commercial dry cleaning plant and the
storage of spare parts. This type of premises afforded little encouragement to rodents
but much of the plant is imported, partially assembled and in large wooden crates, from
Germany via Hamburg and London docks. It seems entirely probable therefore that
occasional crates had provided harbourage for the ship rats which had then been transported
and released in the Richmond factory. The infestation was cleared.
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