Carrion Beetles Visiting Pig Carcasses during Early Spring in Urban, Forest and Agricultural Biotopes of Western Europe

Carrion beetles are important in terrestrial ecosystems, consuming dead mammals and promoting the recycling of organic matter into ecosystems. Most forensic studies are focused on succession of Diptera while neglecting Coleoptera. So far, little information is available on carrion beetles postmortem colonization and decomposition process in temperate biogeoclimatic countries. These beetles are however part of the entomofaunal colonization of a dead body. Forensic entomologists need databases concerning the distribution, ecology and phenology of necrophagous insects, including silphids. Forensic entomology uses pig carcasses to surrogate human decomposition and to investigate entomofaunal succession. However, few studies have been conducted in Europe on large carcasses. The work reported here monitored the presence of the carrion beetles (Coleoptera: Silphidae) on decaying pig carcasses in three selected biotopes (forest, crop field, urban site) at the beginning of spring. Seven species of Silphidae were recorded: Nicrophorus humator (Gleditsch), Nicrophorus vespillo (L.), Nicrophorus vespilloides (Herbst), Necrodes littoralis L., Oiceoptoma thoracica L., Thanatophilus sinuatus (Fabricius), Thanatophilus rugosus (L.). All of these species were caught in the forest biotope, and all but O. thoracica were caught in the agricultural biotope. No silphids were caught in the urban site

Lesion regeneration capacities in populations of the massive coral Porites lutea at Réunion Island: environmental correlates

The capacity of corals for repairing partial mortality is a fundamental determinant of reef resilience. This capacity was assessed in the major reef-building coral Porites lutea by monitoring the regeneration of artificially induced lesions of standard size (330 ± 50 mm2, 3 mm deep) in 4 shallow reef flat populations at Réunion Island, under different environmental conditions related to sites and seasons, during a period without positive temperature anomalies. An exponential decay model with an asymptote described the lesion regeneration through 14 experiments. In spite of fast initial lesion regeneration, limited capacity for repair in this massive coral was indicated, as only 18% of the inflicted lesions healed completely within 6 to 9 mo. Lesion regeneration was fastest and most complete in the cooling and cool seasons, and may be impaired during the warming and hot seasons. Both solar radiation and seawater temperature contributed to seasonal changes in regeneration capacity, although they had opposite effects. While high radiation during the warming season decreased lesion regeneration rate, potentially through reduction of the photosynthetic efficiency of zooxanthellae, high temperature boosted it but also increased the amount of lesion area that could not be regenerated. Study sites were characterised by different temperature and radiation regimes, but these parameters alone could not explain all site effects on lesion regeneration capacity. Additional factors, most probably chronic stress caused by inputs of organic matter and run-off from land, may further compromise the regeneration capacity of corals and the resilience of coral populations

Environmental conditions.

<p>Daily average sea surface temperature (SST; ± SD, gray area) and cumulative daily solar radiation during the experimental period at (<b>a</b>) Planch’Alizé and (<b>b</b>) Kiosque.</p

Biochemical properties of nubbins of <i>Acropora muricata</i> at the onset of the lesion regeneration experiment.

*<p><i>p</i><0.05;</p>**<p><i>p</i><0.01;</p>***<p><i>p</i><0.001.</p

Calcification and lesion healing of <i>Acropora muricata</i>.

<p>Relationship between calcification rates and lesion healing for injured nubbins from Planch’Alizé and Kiosque.</p

Growth of <i>Acropora muricata</i>.

<p>The mean (± SD) relative increase in the projected surface area (‰ d⁻¹) of control and injured nubbins by site.</p