Don’t forget to wear a hat! That should have been my first
thoughts to my companions when we visited Paradise Island. I fortunately did
but my colleagues didn't and got a good smattering of guano for their troubles!
These were proportioned into 1000 each of Long-tailed Cormorant, Cattle and Little Egret, with 80 of Sacred Ibis and 20 of Great Cormorant. The three majority breeders all were having well grown chicks. Also on the island were about 30 Pink-backed Pelican which probably breed at a different time of the year, while other interest was provided by Swamp Flycatcher, Water Thicknee, Orange Weaver and Malachite Kingfisher from over thirty species recorded.
Also present where at least five large Monitor Lizards presumably feeding on the hapless chicks which fall from their nests. These Lizards were remarkably tame and could be approached to within three meters!
Utilising
the derelict chalets are a few fishermen who supplement their diet with small
numbers of Goats and Pigs while in one corner of the island an area of about an
acre has been cleared and planted with Tomatoes. While we were there they were
spraying the Tomatoes using the chemical Dimethoate, this chemical is highly
toxic but here in Africa, no problem! Google it and get the full facts suffice
to say it is pretty lethal
Effects on wildlife
The toxicity of dimethoate for aquatic
organisms and birds is moderate to high. One study found that it causes
temporary rhythm alterations in some bird seed-eating species. Whilst these
effects may not be fatal, they may be critical for the birds’ food-finding
ability and in making them more vulnerable to predators. Dimethoate has also
been found to affect wood mice behaviour and to cause jumping, erratic movement
imbalance and death in fish.
Dimethoate is highly toxic to bees on an acute contact basis; particular
concern has been expressed over this. The LD50 (oral and topical) for bees is
0.1-0.2 µg/bee. Products containing dimethoate are warned not to apply to crops
in open flower nor when flowering weeds are present.
The
above paragraph gives a good idea of the potential hazards; we did notice that
the closest tree to the crop spraying had large number of nestling Long-tailed
Cormorant on the ground which had not been removed by the resident Monitors! Suffice
to say we tried not to breath in too much. The runoff chemicals into Lake
Victoria must affect the local aquatic fauna.
After
a couple of hours on this small but interesting wildlife paradise we departed
on our rickety boat and returned to Bens Beach landing site glad to be on solid
ground once more.
Roger Skeen
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