Is the poor establishment and performance of heather beetle in Tongariro National Park due to the impact of parasitoids predators or disease

Heather beetle (Lochmaea suturalis) introduced in 1996 into Tongariro National Park New Zealand to control heather (Calluna vulgaris) has established poorly and only damaged heather at one site This work investigated whether natural enemies could be reducing heather beetle establishment and impact No egg larval or adult parasitism was found Possible egg predation by a carabid beetle larvae and occasional attacks on larvae by the native pentatomid (Cermatulus nasalis) were observed in the field Neither the microsporidian pathogen discovered in some beetles imported from the United Kingdom nor any other pathogenic diseases were detected in fieldcollected beetles in New Zealand It is suggested that adverse weather was responsible for a collapse in heather beetle numbers at Te Piripiri during 2002 Further efforts to redistribute heather beetle and continued monitoring of beetle numbers impact natural enemies and climate at release sites are recommended

A European pest to control a New Zealand weed: investigating the safety of heather beetle, Lochmaea suturalis (Coleoptera: Chrysomelidae) for biological control of heather, Calluna vulgaris

Heather, Calluna vulgaris (L.) Hull, is a serious invasive weed in the central North Island of New Zealand, especially in Tongariro National Park, a World Heritage Area. Heather beetle, Lochmaea suturalis (Thomson), is a foliage-feeding pest of Calluna in Europe, that was selected as the most promising biological control agent for introduction into New Zealand, because it causes high levels of damage to Calluna in Europe. Host-range tests indicated that L. suturalisposes a negligible threat to native New Zealand plants. Cultivars of Callunagrown as ornamentals are suitable food plants, but are unlikely to be severely affected because L. suturalis requires a damp understorey of moss or litter for successful oviposition and pupation, which is rarely present in gardens. However, mosses and litter occurring under Calluna stands in Tongariro National Park are suitable substrates for eggs and pupae. Lochmaea suturalis released in New Zealand has been freed of parasitoids and a microsporidian disease that attack the beetles in Europe.