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Pest Status
Background
Chapter 24
Tipula paludosa Meigen, European
Cranefly (Diptera: Tipulidae)
A.T.S. WILKINSON
The early history of the European crane fly, Tipula paludosa Meigen, in Canada has
been recorded already (Fox 1957. Wilkinson & MacCarthy 1967. Wilkinson 1971). In
Nova Scotia, this pest peaked about 1965 (Creelman 1971) but had declined to a low level
by 1971. High populations of the larvae (Ieatherjackets) damaged golf courses and lawns
around St. John's, Newfoundland until 1970 (Creelman 1969, 1970). In the lower Fraser
Valley of British Columbia, it has spread as far east as Hope. On Vancouver Island, it
was found near Duncan and Victoria in 1972 and caused damage to golf courses and
lawns in Victoria in 1976. It damaged lawns in Nanaimo in 1978 and in Alberni in 1979. In
1980. it damaged lawns and a golf course in Prince Rupert (Fig. 3). Populations were
highest when the pest was first found in 1965, but as the infestation was spread by gravid
females from the introduction sites near Vancouver into the lower Fraser Valley and
south into Washington State, populations declined, damage became less, and chemical
controls became unnecessary. When new isolated infestations such as those on Vancouver
Island and at Prince Rupert occur, they behave like those near Vancouver did
and require control measures, at least in the first few years. The spread south in
Washington was recorded by Jackson & Campbell in 1975, when crane flies had been
found 180 km south of the British Columbia-Washington border.
No indigenous parasitoids have been found in larvae of T. paludosa but many predaceous
ground beetles and birds have been observed feeding on them. The starling
continues to be the best predator of both the larvae and adults. Many birds feed on the
adults.
One disease, or combinations of the many diseases found in the larvae, may have been
responsible for reducing populations and keeping them below the economic level, but
this has not been proven. The following diseases have been identified in T. paludosa
larvae from the Vancouver area by Dr. P.L. Sherlock, Rothamsted Experimental
Station, Harpenden, Herts., England: Gregarina longa Leger, Hirmocystis venlricosa
(Leger) Labbe, AClinocephaius lipuiae (Hammerschmidt) Leger, DiplocySlis sp. and
Nosema binucleatum Weissenberg. All except N. binucleatum were also found in
larvae from Newfoundland. In British Columbia, up to 50% of the larvae examined
harbour all protozoans mentioned.
The literature indicated that the parasitoid Siphona geniculata De Geer was considered
the primary control agent of T. paludosa. In England, Rennie & Sutherland (1920)
recorded 21.3% and IS.9% parastism for 2 consecutive years for the first generation and
27.7% parasitism for the second generation. The latter was based on a low host population.
Parasitism by S. geniciliala in other parts of Europe was not as high as that reported by
Rennie & Sutherland. The Commonwealth Institute of Biological Control was retained
by Agriculture Canada, Research Branch, in 1967 to study natural controls in Germany
where T. paludosa occasionally causes damage in pastures. Populations of T. paludosa
examined for parasitoids in 3 sites in Germany by Carl (1972) showed parasitism of 15.5,
O.S, and 6.0% for the first generation and 4.9, 4.5, and 4.0% for the second generation. S.
genicuiala has been recorded in Europe from Mamestra brassicae (L.), T. oleracea L., T.
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