The impact of red howler monkey latrines on the distribution of main nutrients and on topsoil profiles in a tropical rain forest

Scarcity of organic matter and nutrients in the topsoil is a typical feature of lowland primary tropical rain forests. However, clumped defecation by vertebrate herbivore troops and further dung beetle processing may contribute to locally improve soil biological activity and plant growth. We studied the impact of clumped defecation by the red howler monkey (Alouatta seniculus), a frugivorous primate, on the vertical distribution of topsoil (0–6 cm) main nutrients and microstructures in a tropical rain forest (French Guiana). Three latrines, where monkey troops regularly defecate, were sampled, together with adjoining controls for carbon, nitrogen, phosphorus and microscopic components. The vertical distribution of C and N was affected by clumped defecation: nutrients were mostly restricted to the top 2 cm in control areas while latrines exhibited homogeneously distributed C and N, resulting in higher C and N content below 2 cm. No marked effect of defecation was registered on Olsen P. A small although significant increase in pH (0.1–0.3 pH units) and a marked increase in soil respiration (×1.5–2.5) were registered in latrines. Soil microstructures were studied by the small‐volume method. Variation according to depth, site and clumped defecation was analysed by Redundancy Analysis. The three latrines were characterized by an increase in root‐penetrated mineral‐organic assemblages, mainly composed of recent and old earthworm faeces. The local stimulation of plant roots, microbial and earthworm activity was prominent, together with an increase in soil fertility. Consequences for the regeneration of tropical rain forests in the Amazonian basin were discussed, in the light of existing knowledge.     

An Artificial Latrine Log for Swamp Rabbit Studies

ABSTRACT Managers use latrine surveys to monitor swamp rabbit (Sylvilagus aquaticus) populations but may miss rabbits in sites lacking suitable latrine logs. We tested artificial latrine logs in logless thickets in southern Illinois, USA, generally detecting swamp rabbits in fewer visits than by live-trapping. Artificial logs can aid swamp rabbit monitoring, especially in logless habitats.     

Seasonal Use of Latrines by Bobcats: Implications for Monitoring Programs

Latrines serve as important communication networks among felids for transmitting information relative to social dominance, reproductive status, and defense of hunting areas. During January 2011–August 2012, we monitored 10 bobcat (Lynx rufus) latrines in the northern Lower Peninsula (NLP) of Michigan, USA, using motion-sensitive cameras to estimate bobcat visitation and scat deposition rates among 3 biological seasons (mating, kitten-rearing, non-mating). Bobcat visitation rates differed among the 3 seasons. We found equal number of visits during the mating and kitten-rearing seasons, and lower visitation rates during the non-mating season. Scat deposition rates differed among the 3 seasons. We found a net gain of scats deposited during the mating and non-mating seasons, whereas there was a net loss of scats during the kitten-rearing season. An artificial latrine protocol we developed yielded visitation at 4 of 12 artificial latrine sites. Monitoring natural and artificial latrines during the mating and kitten-rearing seasons could provide valuable data for managing bobcat populations. © 2020 The Wildlife Society.