Forest disturbance and arthropods: small‐scale canopy and understory disturbances alter movement of mobile arthropods

Abstract

Dispersal of ground-dwelling arthropods is understudied in forest ecosystems, which hinders understanding of effects of disturbances on population dynamics. The objective of the study was to quantify movement of ground-dwelling arthropods in response to a factorial combination of canopy gap formation via girdling and understory vegetation removal, which was shown in a companion study to alter arthropod abundance and species richness. Arthropod movement was quantified using a self-mark-capture technique where arthropods were marked as they crossed three concentric bands of different colored fluorescent powders located 3, 8, and 15 m from the center of 30 9 30 m experimental quadrats. The number of colors found on an individual was considered representative of dispersal such that the more colors detected, the more an individual moved. The likelihood that arthropods were marked with fluorescent powder and the number of colors detected differed among taxonomic groups. Most taxa were marked with one color and a high proportion of those individuals were collected adjacent to the band in which they were marked, suggesting limited dispersal. Canopy gaps and understory vegetation removal influenced movement of three taxa of highly mobile arthropods: Parajulidae and Paradoxosomatidae (detritivores), and Opiliones (scavengers). Opiliones were less likely to be marked with fluorescent powder in canopy gaps than under closed canopy in July, but more likely to be marked in August. Paradoxosomatidae were less likely to be marked in canopy gaps than under closed canopy in August, but their movement was unaffected in July. Parajulidae were more likely to be marked with fluorescent powders when understory vegetation was removed in July and August. Limited dispersal of most other ground-dwelling arthropods suggests that these more sessile taxa may experience decreased survival and reproduction if they are unable to cope with environmental change in response to natural and anthropogenic disturbances. Understanding how disturbances mediate arthropod movement can inform biodiversity conservation strategies and sustainable forest management.

Spread of Bambusa bambos (L.) Voss influences litter‐dwelling arthropod communities in native forests: a case study from Sri Lanka

“…Accordingly, the bamboo spread has the potential to modify the microclimate of the forest floor (Araujo, 2008; Griscom et al, 2013; Rother et al, 2016) by increasing the soil temperature and diminishing the soil moisture (Collins et al, 1985; Fahey & Puettmann, 2007; Gray et al, 2002; Ishizuka et al, 2002; Perry & Herms, 2016). These modifications may create more diverse and suitable niches for arthropods (Perry et al, 2021), thus increasing their abundance and richness.…”

“…Litter‐dwelling arthropods contribute significantly to the arthropod diversity in tropical forests (Bardgett et al, 2005; Novotny et al, 2006; Stork & Grimbacher, 2006), and play a key role in ecosystem functions such as nutrient cycling and carbon sequestration (Costanza et al, 2017; deVries et al, 2013; Jeffery et al, 2010). They are well‐known drivers of many functions in forest ecosystems and are influenced by natural/semi‐natural disturbances (fire, invasion, etc.,) and forest management activities (logging, harvesting and restoration), emphasising their pivotal role as bio‐indicators in monitoring forest health (Hartshorn, 2021; Oliver et al, 2000; Perry et al, 2021). Litter‐dwelling arthropods are involved in the primary decomposition that facilitates the subsequent microbial breakdown of organic matter (Cardenas et al, 2017; Grandy et al, 2016).…”

The Short-Term Responses of Forest Soil Invertebrate Communities to Typhoon Disturbances

“…For instance, Alejandro et al [48] showed that microhabitat destruction and large reductions in lower trophic level species caused by rainfall can make it difficult for predatory functional taxa and soil invertebrates with poor dispersal abilities (e.g., ants and spiders) to survive. In contrast, soil invertebrates with a high dispersal capacity (e.g., beetles) are slightly affected by rainfall [49], and these mobile populations are able to expand their ranges [50] and travel to additional areas to access food resources [51]. We also found that the population density of predators, i.e., Coleoptera and Lepidoptera insects, in CF and SF was higher than that in MF and BF and significantly decreased during the typhoon disturbances (Table S1), which undoubtedly confirms our idea.…”

Beetles on the move: Not‐just‐a‐technical review of beetles' radio‐tracking

“…In some cases, researchers can compromise by using a few tracking devices with a risk of reduced data quantity and subsequent problems with publishing. This obstacle can be partially overcome by using relatively low‐budget methods, such as direct observation (Drees et al, 2008; Cerda et al, 2015), capture‐mark‐recapture (Kagawa & Maeto, 2009; Svensson et al, 2011), or fluorescent powder applied on the ground (Perry et al, 2021). Unfortunately, these approaches have considerable limitations for obtaining detailed movement data suitable for trajectory analyses.…”