We analyzed decade-long time series of water transparency, algal abundance, zooplankton density, heat income, hydrology, and climate from six polymictic lakes of the northern Great Plains to determine how energy and mass transfers interact to regulate lake structure during the spring clear-water phase (CWP). Timing (date of occurrence) and intensity (Secchi transparency) of CWP were highly variable among lakes (mean lake-pair synchrony, S 5 0.072, p 5 0.53); however, CWP occurred in all lakes when water overlying the sediments reached 16.1uC 6 3.7uC and Daphnia cleared the water column of diatoms. At a decadal resolution, timing and intensity of CWP were correlated strongly and positively (r 2 . 0.90, p , 0.05) with the net heat income (h) and lake volume, but not with other independent lake, catchment, or climate features. Instead, at an annual resolution, the strength of correlations between CWP characteristics and heat income (r CWP-h ) was itself correlated inversely with the winter index of the North Atlantic Oscillation (r , 20.55, p , 0.05) and with precipitation during FebruaryApril (r , 20.675, p , 0.05). We conclude that the transfer of energy interacts with lake volume to regulate differences in timing and intensity of CWP among lakes, whereas the transfer of mass overrides energetic regulation to introduce temporal variation in CWP characteristics among years.

Whereas other species of sportive lemurs (genus Lepilemur) have been described as living in dispersed pairs, which are characterized by spatial overlap but a lack of affinity or affiliation between one adult male and female, existing reports on the social organization of the white-footed sportive lemur (Lepilemur leucopus) are conflicting, describing them as either living in dispersed one-male multifemale systems or pairs. We conducted this study in the spiny forest of Berenty Reserve, southern Madagascar, to clarify the social organization and to characterize the level of social complexity of this species. We combined 1530 h of radio-telemetry and behavioral observations over a period of 1 yr to describe the spatiotemporal stability, size, and interindividual overlap of individual home ranges as well as interindividual cohesiveness. Results revealed low intra- and high intersexual home range overlap. Although most of the social units identified consisted of dispersed pairs (N = 5), males were associated with two adult females in two cases. Furthermore, members of a social unit were never observed to groom each other or to share a daytime sleeping site, and Hutchinson’s and Doncaster’s dynamic interaction tests indicated active avoidance between pair partners. Low cohesiveness together with extremely low rates of social interactions therefore arguably places Lepilemur leucopus at the low end of primate social complexity.

We conclude that these animals prioritize protein over non-protein energy intake as dietary protein is in limited supply, and that thermoregulation poses higher energetic costs than reproduction in this species. While protein intake did not differ across female reproductive states, the relative protein content of the diet was highest during the lactation period, indicating that the balance of non-protein to protein intake may be more important than absolute intake. Dry matter intake was high compared to other folivorous primates, indicating that L. leucopus follows an intake rather than an efficiency strategy to meet its energy requirements. Am J Phys Anthropol 160:197-207, 2016. © 2016 Wiley Periodicals, Inc.

Latrine use (i.e., the repeated use of specific defecation/urination sites) has been described for several mammals, including carnivores, ungulates, and primates. However, the functional significance of latrine use in primates has not been studied systematically yet. We, therefore, followed 14 radio-collared individuals of the pair-living white-footed sportive lemur (Lepilemur leucopus) for 1097 hours of continuous focal observations to investigate latrine distribution, seasonality of latrine use, as well as age and sex of users to test various hypotheses related to possible functions of latrine use, including territory demarcation, resource defense, signaling of reproductive state, social bonding, and mate defense. All individuals of a social unit exhibited communal use of latrines located in the core area of their territory, supporting the social boding hypothesis. Latrine use seems to facilitate familiarity and social bonding within social units via olfactory communication in this primate that lives in family units but exhibits low levels of spatial cohesion and direct social interactions. In addition, frequency of latrine visitation was higher during nights of perceived intruder pressure, supporting the mate defense hypothesis. However, animals did not react to experimentally introduced feces from neighboring or strange social units, indicating that urine may be the more important component of latrines than feces in this arboreal species. Based on a survey of latrine use and function in other mammals, we conclude that latrines facilitate communication particularly in nocturnal species with limited habitat visibility and in species where individuals are not permanently cohesive because they constitute predictable areas for information exchange.Electronic supplementary materialThe online version of this article (doi:10.1007/s00265-014-1810-z) contains supplementary material, which is available to authorized users.

1. This study examined the abundance and distribution of freshwater sponges (Spongillidae) at 32 sites in a floodplain on the Danube within the 'Donau-Auen' National Park east of Vienna, Austria. Ranked from abundant to rare, the species inventory comprised Ephydatia fluviatilis, Spongilla lacustris, Ephydatia mü lleri, Eunapius fragilis and Trochospongilla horrida. 2. The presence of hard substratum was essential for the growth of sponges. Timber stands near the water and drifting dead wood increased the abundance of E. fragilis, E. fluviatilis and E. mü lleri, whereas stony substrata were important for S. lacustris. A small fraction of E. fluviatilis was collected from macrophytes (Phragmites). 3. Based on the area colonised, the abundance of S. lacustris, E. fragilis and E. fluviatilis was highest (94.2-100% of the total) in floodplain waters where hydrological connectivity with the Danube was low (0-6 days year )1 ), whereas E. mü lleri and T. horrida made up 20.3-35.9% of the total at sites connected for up to 179 days year )1 . Moreover, the area colonised by T. horrida at a current velocity >0.20 m s )1 was larger than in the remaining species. Sites with E. mü lleri and T. horrida had a higher silicon concentration (0.9 mg L )1 ) than sites where the remaining three species were collected (0.4-0.6 mg L )1 ). 4. In most species, the length of macroscleres (the larger spicules) was positively correlated with conductivity and negatively with pH. With respect to aberrant macroscleres, hooks were observed most frequently, whereas the proportion of centrotylotes (ie with the one on more globular swellings along the spicule) was lowest. 5. Freshwater sponges have a great deal of potential as bioindicators and restoration measures that improve floodplain connectivity will favour rare species, such as E. mü lleri and T. horrida, while impairing others (e.g. E. fragilis, S. lacustris and E. fluviatilis).