Seasonality and life histories of two endemic New Zealand carabid beetles (Coleoptera: Carabidae):Mecodema oconnoriBroun andMegadromus capito(White)

Abstract

Seasonal activity and life histories of two large endemic carabid beetles, Mecodema oconnori Broun and Megadromus capito (White), were investigated in two lowland forest remnants in the Horowhenua region, North Island, New Zealand. Seasonal activity was estimated from manual searches of surface refuges, plus pitfall trapping from October to March. Adults of both species were present throughout the year, although M. oconnori was much more abundant in spring. Megadromus capito larvae were caught from October to March, and the three instars overlapped temporally, implying a long period of larval emergence and development. Adult females were dissected to investigate their reproductive phenology. Both species carried eggs for at least 6 months of the year. M. oconnori females contained very few eggs, with a maximum of three eggs each and a mean of 1.6 eggs per female. Mg. capito females had up to 28 eggs each and a mean of 10.5. Both species appear to have low egg loads, a relatively long period of reproductive activity and long life spans, but longer-term studies on the pre-adult stages and reproductive activity of adults are required to complete understanding of their life cycles.

Pitfall trap sampling bias depends on body mass, temperature, and trap number: insights from an individual‐based model

“…Population density of ground arthropods varies across years and habitats; though, limited knowledge exists about how accurate the sampled density reflects variation in the real density (Collins et al 2003, Hutchison 2007, Woodcock 2005. Variation in the ambient temperature can produce considerable bias in pitfall sampling because the locomotory activity of most ground arthropods varies with ambient temperature, and sampled densities are proportional to locomotory activity (Thomas et al 1998, Woodcock 2005.…”

Effect of boundary type and season on predatory arthropods associated with field margins on New Zealand farmland

“…Whereas Carabidae adults were observed throughout the sampling period (Hutchison 2007), the staphylinid beetles and coccinellids were much more seasonal, with clear peaks in abundance. The spiders also showed distinct peaks in abundance over the sampling period, although these tended to be different times of the year for the different species ( Fig.…”

When to sample in an inaccessible landscape: a case study with carabids from the Allgäu (northern Alps) (Coleoptera, Carabidae)

“…His classification of carabids’ annual rhythms was elaborated upon and modified by other carabidologists ( Lindroth 1949 ; Thiele 1977 ), and the importance of reproductive behaviour as a life history trait in carabids was emphasized by den Boer and van Dijk (1998) and Paarmann (1979) . Many studies have dealt with the relationship between activity patterns and habitat preference, and these studies have lead to a better understanding of distribution trends and specific habitat adaptations of carabids ( Lys and Nentwig 1991 ; Riddick and Mills 1995 ; den Boer and van Dijk 1996 ; Matalin 1997 ; Fadl and Purvis 1998 ; Traugott 1998 ; Hutchison 2007 ).…”