influence of temperature on the duration of egg development in West European grasshoppers (Orthoptera: Acrididae)

• Published in: Oecologia 1991-09, Vol.87 (3), p.417-423
• Main Authors: Wingerden, W.K.R.E. van, Musters, J.C.M, Maaskamp, F.I.M
• Format: Article
• Language: English
• Subjects: Acrididae; Animal and plant ecology; Animal, plant and microbial ecology; Animals; Autoecology; Biological and medical sciences; Chalk grasslands; Eggs; embryogenesis; eutrophication; Fundamental and applied biological sciences. Psychology; Grasshoppers; Grassland management; Grassland soils; grasslands; Habitat conservation; Hatching; Invertebrates; Premenstrual syndrome; Protozoa. Invertebrata; Soil temperature regimes; Surface temperature; temperature; vegetation; vegetation structure
• ISSN: 0029-8549; 1432-1939
• DOI: 10.1007/BF00634600

The relationship between embryonic postdiapause development (PDD) and temperature in ten Acridid species was studied by culturing eggpods from diapause onwards at constant temperatures (ranging from 15.0° C to 37.5° C). In six species PDD was also studied at fluctuating temperatures (12 h at 27.5° C and 12 h at 13.0° C). The PDD duration was strongly temperature dependent in all species studied (Q10values between 3.0 and 4.1) and differed greatly between species. To assess whether these differences affect habitat determination, PDD duration was related to habitat microclimate. We found that species with a relatively long PDD are restricted to relatively warm grasslands, while species with a short PDD are also found in colder grasslands. Two species have a more limited occurrence than predicted from PDD duration. It is argued that the length of PDD (and consequently hatching date) is crucial to the completion of the annual cycle. The results are applicable to conservation of grasshoppers in grasslands subject to eutrophication. Here increase of vegetation density and height will lead to lower maximum temperatures in the egg environment (i.e. near the soil surface) and consequently to a delay in hatching and loss of thermophilous species. Grassland management rules are proposed that should aid conservation of these species.