The effects of grazing and mowing on large marsh grasshopper, Stethophyma grossum (Orthoptera: Acrididae), populations in Western Europe: a review

Abstract

The large marsh grasshopper, Stethophyma grossum L. (Orthoptera: Acrididae), has undergone a significant range contraction in the UK and is now restricted to the bogs and mires of the New Forest and Dorset Heaths. In other parts of Western Europe, the species makes use of a wider range of wetland habitat types. Traditionally, many of these habitats would be managed through low intensity grazing, mowing, or both, and these measures are now often employed in the conservation management of wet grassland habitats. This paper reviews the effects of mowing and grazing on S. grossum populations, through looking at the potential impacts (both positive and negative) on different life stages of the grasshopper. Both techniques are valuable in the maintenance of an open and varied vegetation structure which is known to benefit S. grossum in all its life stages. However, grazing on very wet sites or at high intensity can result in trampling of vegetation and S. grossum eggs, and mowing which is too frequent may negatively affect populations through repeated losses of nymphs. Recommendations are given regarding the suitability of mowing and grazing for different habitats and intensity of management to generate the required vegetation structure. Measures are also outlined, such as the provision of unmown or ungrazed refuge areas, which can help reduce negative effects.

How expert insight into alpine peatland conservation complements global scientific evidence

“…In Europe, some hooved herbivores are native to peatlands (Lindsay et al., 2014). In those systems, low‐intensity grazing by ponies or cattle (or mowing to mimic grazing) is used to manage vegetation structure, composition, and encroachment (Miller & Gardiner, 2018), although it can negatively alter these ecosystems too (Rowland et al., 2021). Second, the unique characteristics of individual ecosystems can influence the suitability or implementation of interventions.…”

Large‐scalePVAmodeling of insects in cultivated grasslands: The role of dispersal in mitigating the effects of management schedules under climate change

“…In terms of our model, the impact of mowing on the model species is exclusively negative, although of different magnitude with respect to the above‐ and belowground life stages. Indirect effects of mowing, e.g., the observation that an early and/or late cut could maintain a beneficial vegetation structure for the species (Malkus, 1997; Miller & Gardiner, 2018; Sonneck et al, 2008), are not included in the model. However, such low‐impact maintenance cuts with only a minor mortality effect on the LMG are accounted for by the base mowing schedule named M20 + 00 + 44 (acronym: M00 ) that stands for an undisturbed environment and always takes effect where no other schedules apply.…”

Large scale PVA modelling of insects in cultivated grasslands: the role of dispersal in mitigating the effects of management schedules under climate change

“…Indirect effects of mowing, e.g. the observation that an early and/or late cut could maintain a beneficial vegetation structure for the species (Malkus, 1997; Miller and Gardiner, 2018; Sonneck et al, 2008), are not included in the model. However, such low-impact maintenance cuts with only a minor mortality effect on the LMG are accounted for by the base mowing schedule named M20+00+44 (acronym: M00 ) that stands for an undisturbed environment and always takes effect where no other schedules apply.…”