There is increasing awareness that structure-based indicators should be considered for assessing the biological value of late successional forests. In order to increase the unique habitat features critical for old-growth associated species, it is important to identify and rank candidate potential forest sites on the basis of their distinctive structural features. Data on living and deadwood components for the identification of old-growth condition are usually acquired in the considered forest stands by two sampling survey: (i) census performed in relatively large monitoring sites; (ii) network of small sampling units, on which inventory practices are usually based. Several authors argued that choosing between these survey strategies might have substantial effects on the values of common indicators of old-growth condition. Our study aims at (i) assessing the total estimate differences among old-growth structural indicators measured in field plots with different sizes, and (ii) defining the optimal sample size for the reliable assessment of such indicators. The study was carried out in six beech dominated forest stands on the Apennines range in Italy. In each stand, living and deadwood components were surveyed and geocoded in 1-ha square areas. Based on these dataset, circular plots with radii ranging from 4m up to 20m were then considered in order to quantify the effect of sampling plot size on the estimation of four structural indicators: (1) number of living trees; (2) number of large trees (dbh≥50cm); (3) total deadwood volume; (4) number of deadwood elements (snags, dead standing trees; lying dead trees, lying deadwood) with dbh (or average diameter for lying deadwood) ≥ 30cm. We found that the size of the sampling plots should be at least 500 m² in order to establish a database for the assessment of the investigated indicators. The census approach should be preferred to the sampling plot approach for old-growth forest stands smaller than 3-5ha. The achieved results contribute to define assessment protocols for characterizing and ranking the degree to which forest stands approximate old-growth condition based on standardized indicators. © 2015 Elsevier B.V.

Reproductive synchrony among gregarious mammals has a strong adaptive value and may lead to cooperative behaviors aimed at maximizing offspring survival. Additionally, temporal clustering of estrus has important implications on individual mating tactics and ultimately affects the degree of polygamy in a population. Although several studies have examined the reproductive biology of wild boar (Sus scrofa), much remains to be understood about the patterns of timing and synchrony of reproduction in natural populations. We analyzed the spatiotemporal distribution of conception dates in an Italian wild boar population taking into account the effects of environmental and individual factors, in order to determine the main variables influencing the timing of reproduction and to detect the signs of a socially-driven reproductive synchrony. Specifically, for each litter belonging to 354 pregnant sows culled between 2006 and 2013 in a mountain area of Tuscany, we determined the conception date (CD) from an estimate of the mean fetal age and the culling date. We then investigated which factors drove the variation in CD, by implementing linear mixed models, Mantel tests and spatial autocorrelation analyses. The selected model showed significant effects of rainfall, temperatures, and previous and current productivity on CD, as well as a strong correlation of CDs among sows culled in close spatial and temporal proximity (i.e., in the same hunting ground and hunting season). Likewise, autocorrelation analyses and Mantel tests consistently indicated that closer sows had similar conception dates. Overall, our results confirm the effect of resource availability and climate on wild boar reproductive phenology, and suggest socially-driven reproductive patterns, in spite of a high turn-over in social groups due to hunting. Finally, possible advantages and evolutionary implications of reproductive synchrony in wild boar are discussed. © 2015 Associazione Teriologica Italiana.