European red mite - Natural enemies

European red mite is attacked by a wide range of insect predators and mite predators. Biological control by predators plays a major role in orchard mite management in conventional, integrated and organic fruit production.

The most important natural enemy of European red mite in New Zealand is the predatory mite Typhlodromus pyri Scheuten. It is one of a group of predators (called 'typhs') in the family Phytoseiidae which feed on pest mites such as European red mite, twospotted spider mite, and rust mites. T. pyri was probably accidentally introduced into New Zealand with early European settlement and is common throughout the country. It feeds preferentially on European red mite and rust mites, and research has shown that it is capable of regulating (controlling) European red mite populations in apple orchards, provided the use of chemicals toxic to T. pyri is avoided. This has been made easier by the fact that T. pyri has developed resistance or tolerance to many pesticides used in orchards. This enabled the introduction of integrated mite control to New Zealand pipfruit orchards in the 1970s, and as pesticides have become more selective (i.e. less toxic to predators), T. pyri continues to play a major role in control of European red mite. As a result, miticide use in commercial pipfruit orchards has declined.

Other phytoseiid predatory mites which feed on European red mite are:

Neoseiulus (=Amblyseius) fallacis (Garman) - was introduced to New Zealand from Michigan, U.S.A. in 1972, 1973, and 1975. The introduced strain was resistant to organophosphate insecticides. It established successfully, particularly in Canterbury and Marlborough, but preferred to feed on twospotted spider mite rather than European red mite. Although still present in commercial orchards, N. fallacis is encountered infrequently.

Galendromus (= Metaseiulus, Typhlodromus) occidentalis (Nesbitt) - was introduced to New Zealand from Australia in 1976, primarily for the control of twospotted spider mite. It established in a number of regions and has become an important agent for the biological control of orchard mites in Central Otago. While twospotted spider mite is its preferred prey, it also feeds on European red mite. The strain of G. occidentalis introduced to New Zealand was resistant to organophosphate insecticides.

Neoseiulus cucumeris (Oudemans) - is thought to have been accidentally introduced to New Zealand. It is known to be a predator of European red mite and occurs commonly in a range of unsprayed crops, including pipfruit orchards. As the orchard chemicals used for pest management become more selective, this predator may provide an increasing contribution to mite control.

Phytoseiulus persimilis Athias-Henriot - was first introduced to New Zealand from United Kingdom in 1967 for the control of twospotted spider mite, particularly in greenhouses. The initial release did not establish successfully but further material of an 'outdoor strain' was introduced from the south of France in 1977 and 1978. These predators established and became widespread. P. persimilis prefers to feed on twospotted spider mite but commonly attacks European red mite when it is present on the same plants. P. persimilis, sold as 'Mite-E', can be purchased for release into crops, particularly those attacked by twospotted spider mite.

The distribution of the three most important typh species in New Zealand is summarised in the Table.

Other natural enemies of European red mite are:

Agistemus longisetus Gonzalez - a stigmaeid mite predator which feeds on a variety of mite species, including European red mite, Bryobia spp., tarsonemids, and tydeids.

Anthocoris musculus (Say) - is a predatory anthocorid bug introduced to New Zealand from Nova Scotia, Canada in 1965-66. There is no evidence of successful establishment.

Anthocoris nemorum (L.) - is a predatory anthocorid bug introduced to New Zealand from the United Kingdom in 1965-67. Despite the release of 1,000 - 2,000 bugs, there is no evidence of successful establishment.

Anystis baccarum (L.)(= Anystis agilis (Banks)) - this predatory mite is known as the whirligig mite. It feeds on a wide variety of small insects and mites, and this includes the European red mite.

Apterygothrips collyerae Mound and Walker - a predatory thrips known to feed on European red mite, and with a preference for summer eggs.

Arthrocnodax sp. - is a genus of predatory midges (Cecidomyiidae) whose larvae feed on mites, including European red mite.

Cryptoscenea australiensis (End.) - this lacewing (Coniopterygidae) has been recorded as a predator of mites in Auckland apple orchards.

Bdellid mites - are reported as predators of European red mite.

Blepharidopterus angulatus (Fallen) - is a predatory mirid bug (the black-kneed capsid) from the United Kingdom which was introduced to New Zealand in Nelson in 1966. Although nymphs of this species were recovered for several seasons after the releases, it apparently failed to establish.

Cardiastethus spp. - is an endemic genus of predatory anthocorid bugs, reported to feed on European red mite. There are two species which occur occasionally in pipfruit orchards, C. poweri and C. consors.

Cheyletid mites - are reported as predators of European red mite.

Haplothrips kurdjumovi Karny (= H. faurei) - is a predatory thrips which feeds on a variety of small insects and mites, including European red mite. It occurs frequently in pipfruit orchards, particularly in Otago.

Hyaliodes harti Knight - is a predatory mirid bug introduced to New Zealand from Nova Scotia, Canada in 1966. Only small numbers were released and they apparently failed to establish.

Orius vicinus (Ribault) - a predatory anthocorid bug which was first reported in Central Otago, New Zealand in 1994. It appears to have been introduced accidentally and has become common and widespread in Otago. It has spread north to Canterbury. European red mite is among its preferred prey.

Sejanus albisignata (Knight) - a predatory mirid bug, which is thought to be an accidental introduction to New Zealand early in the 20th century. It commonly feeds on European red mite. The nymphs of the bug are brick red in colour while the adult is black with two characteristic white flecks, one each side of the wings midway down the back.

Spiders - there are many reports of spiders feeding on a variety of mite species in different parts of the world. Predation of European red mite by spiders has not been studied in New Zealand.

Staphylinids (rove beetles) - include some species which are predatory on spider mites but this has not been studied in New Zealand.

Stethorus bifidus Kapur - is a small shiny black ladybird (Coccinellidae), about 1mm long, which is the most common insect predator of European red mite in pipfruit orchards. Another similar-looking species, Stethorus histrio occurs in more northern regions. The larvae are cigar-shaped, predominantly buff and grey in colour and 3-4mm long. Both the adult beetles and the larvae feed almost exclusively on mites. S. bifidus has several generations a year, depending especially on host numbers and distribution. The adults are highly mobile and can quickly locate isolated mite populations in spring, and may prevent them from establishing in orchards. Later in the season they may work with phytoseiid mites to bring large populations of plant-feeding mites under control.

Syrphidae - Larvae of several syrphid flies have been observed to feed on all stages of European red mite (overseas).

Zetzellia sp. - this genus of stigmaeid mites (especially Z. mali (Ewing)) has been reported as a predator of European red mite.