2005 - Whitby Naturalists

BEETLES
Early this year I had a few enciuiries about Ladybirds. The B.B.C.
Springwatch Survey had postcards falling out of magazines to record
sightings, including the ?-spot Ladybird' This may have madc people
rnorc aware of Ladybirds, and sorne, findrng small Z-spot Ladybirds,
quite logically wondcred if they would grow into the larger 7"spot. The
answcr is "No".
Sr',me books arc mislear{ing, as thcy tlon't make clcar the different stzcs
of the species.
Thcre are twenry-four species, which would normally be thought of as
British. They pass through three stages - egg, larva, and pupa before
rcaching thc adult stage; rhis cy'clc raking a ycar in many species-
Eggs are laid in Spring or early Summer near a colony of aphids, and
rake 7-4 days to hatch dcpending on the amhient ternperature. 'fhe
larvae feed over the next month or so, the timc again varying with the
temperaturc and the number of aphids available- Diring this stagc
they shcd thcir skins three times before pupating. One or two wceks
later the adult emerges. The elytra (wing cases) are a plain vcry light
yellow or orange at first. The adult colours and spots may take several
hours or cven days to deveiop. In those having a red background
colour this gradually deepens ovcr weeks or months, so newlv emerged
adults can be distinguished from those which have ovet'wintered, as
chese are a inuch deeper shade of recl
Most adults emerge in urid - to late summel and feed ftlr several weeks
be{ore going to their hibemating sites in Scptember or early October.
lv{aring mostly takcs place in the spring and the number of eggs lai-d can
vary with the sort of aphid eaten. Although some species of Ladybird
are very variablc in colour and pattcrn, once they have developed this
colour and pattern it will not change any further except for darkening
with age
The August edition of the British Vildlife magazine had an article
about the Harlequin Ladybird, a new invasive species. It is a voracious
eater of aphids but also preys on native Ladybird trarvae. Although thcy
eat a lot of aphids, tirat good point is spoilt by them eating other
beneficial insects and some soft fruits.
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