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Theory on the density?body-mass (DBM) relationship predicts that the density of animal species decreases by the power of ?0.75 per unit increase in their body mass, or by the power of ?1 when taxa across trophic levels are studied. This relationship is, however, largely debated, as the slope often deviates from the theoretical predictions. Here, we tested the ability of the DBM relationship to reflect changes in the structure of communities subjected to an anthropogenic disturbance. The slope would become less steep if smaller animals were more impacted by the disturbance than the larger ones, whereas the slope would become steeper if larger animals were more affected than the smaller ones. We tested the changes in the DBM relationship by sampling soil fauna, i.e., nematodes, Collembola, and larger arthropods, from a semiarid grassland before and after spraying diesel fuel as disturbance. We applied three different treatments: a control, a light disturbance, and an intense disturbance. We found that the slopes of the DBM relationships before the disturbance were around ?1 as predicted by theory. The slope became more positive (i.e., less steep) just after the disturbance, especially after the intense disturbance as smaller fauna suffered the most and early colonizers had larger body mass. Interestingly, we observed that the slopes converged back to ?1 by 2 months post-disturbance. Our findings show that the response of soil fauna communities to anthropogenic disturbances could explain the large variation in observed slopes of the DBM relationships. We experimentally demonstrate that an animal community, when disturbed, shows a temporal pattern of DBM relationships ranging from deviations from the predicted slope to convergence to the predicted slope with time. We recommend that deviations in the DBM relationships after disturbances can provide insights in the trajectory of community recovery, and hence could be used for biomonitoring.

Retraction notice: We have been informed that because of logistical reasons the authors of Comor et al. (2019) were unable able to provide the answers requested by Duriez et al. (2020) regarding the protocols, the quantitative data, or the small and unbalanced sample sizes. At the authors' request, the article by Comor et al. published in Human–Wildlife Interactions 13(3) has been retracted. Human activities are usually considered as disturbing factors impeding the breeding success of wild animals. Protected areas can then be set up to restrict such activities aiming to improve wildlife’s breeding success and conservation. To test for the efficiency of these measures, we compared the breeding success of bearded vultures (Gypaetus barbatus) in the western French Pyrenees from autumn 2011 to spring 2017, where eyries are located either within or outside restricted areas, where potentially disturbing activities are restricted (e.g., helicopter flights, forestry works, hunting, paragliding). We monitored reproducing bearded vultures and checked the breeding success at different stages (laying, incubation, hatching, and survival at 2 months) of formed pairs. We then compared the success of each stage between eyries located in restricted and non-restricted areas, including weather data in our model. We found that the breeding success was similar in both types of areas, but that is was negatively impacted by precipitations, which may directly affect the ability of the egg or chick to withstand cold. We also focused on the potential disturbance of hunting parties on the behavior of bearded vultures and found no evidence that hunting was perceived as a threat by bearded vultures; they may in fact benefit from gut piles. Hence, our comparison of the breeding success between eyries located in restricted versus non-restricted areas shows no detrimental impact of human activities and calls for some studies to assess the effectiveness of restrictions in improving the breeding success of bearded vultures, as this species seems to show some degree of tolerance to human activities and may significantly suffer from harsh winter weather in this area.