Comparative population studies of threePieris butterflies,P. rapae,P. melete andP. napi,living in the same area

The adult populations of three Pieris butterflies, P. rapae, P. melete and P. napi, were studied in an area of their coexistence throughout the flight seasons by using the mark-and-recapture method. The study area, about 3×1.5 km, was set up in a farm village surrounded by the mountainous area in Inabu, Aichi Prefecture. The habitats were qualified by the four factors, i. e., oviposition plants, adult nector plants, roosting-sites and light conditions. Between P. rapae and P. napi, there were sharp differences with regards to overall habitat preferences. P. melete had the widest preferences for all the habitat resources, which overlapped greately with requirements of P. rapae and P. napi. P. melete and P. rapae showed similar preferences for oviposition plants, but the former preferred shaded habitats while the latter preferred sunny places. P. melete and P. napi, having similar preferences for shaded situations, showed differences in the preferences for oviposition plants. Moreover, three species of Pieris were different in their preferences for adult nector plants. Thus, they were more likely to partition habitat resources rather than competing for them. The habitat structures of each species in respect of time, space and stability to weather changes were much different each other in the same area. The habitat of P. rapae was temporary, localized and unstable. While, that of P. melete was more permanent, widespread and stable than that of P. rapae. P. napi seemed to live in the intermediate habitat, i. e., permanent, localized and stable one.     

Comparative population studies of threePieris butterflies,P. rapae,P. melete andP. napi,living in the same area

Utilization of patchy habitats by adult populations of three Pieris butterflies, P. rapae, P. melete and P. napi was studied throughout the flight season in an area of their coexistence, about 3×1.5 km, in a farm village in the mountains in Inabu, Aichi Prefecture. Field study was by the mark-recapture method. Results were analyzed by dispersal distances and recapture duration decay curves for adults of different age-classes estimated on the basis of physical condition of their wings, together with supplementary information of daliy egg-laying rate of females, obtained in field cages. Sexually immature, mated femals of P. rapae after teneral stage showed a migratory flight. On the other hand, reproductive females and all males of P. rapae were strongly resident within suitable habitats, and reproductive females begun to lay eggs abundantly at sunny places of newly suitable areas within a short period. P. melete seemed to disperse gradually from emerged stites and females of this species continued to lay some constant numbers of eggs for more than ten days over a wider area. P. napi appeared more like P. melete than P. rapae. The habitats of the three species can be characterized as follows:P. rapae, temporary, continued for pre-reproductive females but localized for reproductive females and all males, and unstable;P. melete, permanent, widespread, and stable;P. napi, permanent, localized, and stable. The numbers of generations of P. rapae, P. melete and P. napi were estimated to be about six, three and three, respectively. Seasonal fluctuations in the number of adults were influenced by the stability of their habitats, i. e., the population size fluctuated sharply in P. rapae, but it was much more stable in P. melete and P. napi. In view of these results, it can be said that P. rapae fits the general characteristics of a r-strategist whereas P. melete and P. napi are more K-strategic than P. rapae.     

The role of parasitoids in evolution of habitat and larval food plant preference by three Pieris butterflies

This article attempts to explain that parasitoids provide the evolutionary pressure responsible for relationships between habitat use and larval food plant use in herbivorous insects. Three species of butterflies of the genus Pieris, P. rapae, P. melete, and P. napi use different sets of cruciferous plants. They prefer different habitats composed of similar sets of cruciferous plants. In our study, P. rapae used temporary habitats with ephemeral plants, P. melete used permanent habitat with persistent plants, although they also used temporary habitats, and P. napi used only permanent habitat. The choice experiment in the field cages indicated that each of the three butterfly species avoided oviposition on plants usually unused in its own habitat, but accepted the unused plants which grew outside its own habitat. Their habitat use and plant use were not explained by intrinsic plant quality examined in terms of larval performance. Pieris larvae collected from persistent plants or more long lasting habitats were more heavily parasitized by two specialist parasitoids, the braconid wasp Cotesia glomerata and the tachinid fly Epicampocera succincta. The results suggest that Pieris habitat and larval food plant use patterns can be explained by two principles. The evolution of habitat preference may have been driven by various factors including escape from parasitism. Once habitat preference has evolved, selection favors the evolution of larval food plant preferences by discriminating against unsuitable plants, including those which are associated with high parasitism pressures. Received: December 3, 1998 / Accepted: January 20, 1999     

Factors influencing the radiative surface temperature of grey seal (<Emphasis Type="Italic">Halichoerus grypus</Emphasis>) pups during early and late lactation

The aim of this study was to examine the variation in body surface temperature of grey seal (Halichoerus grypus) pups throughout lactation in response to different environmental conditions. Radiative surface temperatures (T _r, °C) of pups were measured on the Isle of May (56°11′N, 02°33′W), southeast Scotland from 29 October to 25 November 2003. Records were obtained from a total of 60 pups (32 female and 28 male) from three different pupping sites during early and late lactation. Pups were sheltered from high wind speeds but air temperature, humidity and solar radiation at pupping sites were similar to general meteorological conditions. The mean T _r of all pups was 15.8°C (range 7.7–29.7°C) at an average air temperature of 10.2°C (range 6.5–13.8°C). There was no difference in the mean T _r of pups between early and late lactation. However, the T _r varied between different regions of the body with hind flippers on average 2–6°C warmer than all other areas measured. There was no difference in mean T _r of male and female pups and pup body mass did not account for the variation in T _r during early or late lactation. Throughout the day there was an increase in the T _r of pups and this explained 20–28% of the variation in T _r depending on stage of lactation. There was no difference in the mean T _r of pups between pupping sites or associated with different substrate types. Wind speed and substrate temperature had no effect on the T _r of pups. However, solar radiation, air temperature and relative humidity accounted for 48% of the variation in mean T _r of pups during early lactation. During late lactation air temperature and solar radiation alone accounted for 43% of the variation in T _r. These results indicate that environmental conditions explain only some of the variation in T _r of grey seal pups in natural conditions. Differences in T _r however indicate that the cost of thermoregulation for pups will vary throughout lactation. Further studies examining intrinsic factors such as blubber thickness and activity levels are necessary before developing reliable biophysical models for grey seals.     

Spatio-temporal distribution patterns of two tachinid flies,Epicampocera succincta andCompsilura concinnata parasitizingPieris

Larvae of genus Pieris in the northern part of Kyoto City are parasitized by two tachinid flies:Epicampocera succincta, a specialist on genus Pieris, and Compsilura concinnata, a generalist with very wide host-range. We surveyed the parasitism rates of Pieris by both flies for two years at six study areas. In these study areas, there lived three host species in the genus Pieris: P. rapae, P. melete, and P. napi, but neither tachinid parasitized P. napi to any significant extent. In the mountainous district, P. rapae and P. melete coexisted and their populations were relatively continuous, while in the lowland, only P. rapae larvae were abundant in spring and autumn, but even they disappeared in summer. Parasitisms by E. succincta occurred mainly in mountainous district and never in the lowland. C. concinnata parasitized Pieris in all the areas, but its parasitisms occurred mainly in autumn. We analyzed the factors affecting the spatial and temporal patterns of parasitism rates and presumed that the temporal discontinuity of host population restricted the distribution of the specialist parasitoid.     

Preference for C4 shade grasses increases hatchling performance in the butterfly,Bicyclus safitza

The Miocene radiation of C₄ grasses under high‐temperature and low ambient CO₂ levels occurred alongside the transformation of a largely forested landscape into savanna. This inevitably changed the host plant regime of herbivores, and the simultaneous diversification of many consumer lineages, including Bicyclus butterflies in Africa, suggests that the radiations of grasses and grazers may be evolutionary linked. We examined mechanisms for this plant–herbivore interaction with the grass‐feeding Bicyclus safitza in South Africa. In a controlled environment, we tested oviposition preference and hatchling performance on local grasses with C₃ or C₄ photosynthetic pathways that grow either in open or shaded habitats. We predicted preference for C₃ plants due to a hypothesized lower processing cost and higher palatability to herbivores. In contrast, we found that females preferred C₄ shade grasses rather than either C₄ grasses from open habitats or C₃ grasses. The oviposition preference broadly followed hatchling performance, although hatchling survival was equally good on C₄ or C₃ shade grasses. This finding was explained by leaf toughness; shade grasses were softer than grasses from open habitats. Field monitoring revealed a preference of adults for shaded habitats, and stable isotope analysis of field‐sampled individuals confirmed their preference for C₄ grasses as host plants. Our findings suggest that plant–herbivore interactions can influence the direction of selection in a grass‐feeding butterfly. Based on this work, we postulate future research to test whether these interactions more generally contribute to radiations in herbivorous insects via expansions into new, unexploited ecological niches.     

Host preference variation cannot explain microhabitat differentiation among sympatric Pieris napi and Pieris rapae butterflies

1. Often, closely related insect species feed on different host plant species, and the tremendous diversity of phytophagous insects is therefore attributed to host plant‐driven speciation. However, for most taxa, host use information comes from field observations of egg‐laying females or feeding caterpillars, which means that the underlying reason for a particular host‐affiliation is not easily determined. 2. Therefore, it is often unclear whether an insect feeds on a certain host because it prefers that plant to alternative hosts, or because the host distribution overlaps with the habitat requirements of the insect. 3. We ask to what extent a divergent host use in the field mirrors the host plant preferences of two closely related butterflies, Pieris napi and Pieris rapae (Pieridae). In nature, P. napi typically occurs in moister habitats than P. rapae. 4. We scanned several microhabitats at a field site in Southern Sweden during multiple years, and collected Pieris eggs from three different plants, Cardamine pratensis (wet meadows), Barbarea vulgaris (drier micro‐habitats) and Alliaria petiolata (intermediate areas). 5. As predicted, P. rapae eggs were more common than P. napi eggs on B. vulgaris, whereas all of the 358 individuals collected from C. pratensis were P. napi, indicating a divergence in host use between the Pieris species. However, under controlled laboratory conditions, both species had virtually identical oviposition preferences, laying eggs on all three plants, notably P. rapae also laying eggs on C. pratensis, indicating that habitat use, not plant preference, drives host plant use in nature.     

Thermal comfort of sows in free-range system in Brazilian Savanna

The aim of this work was to evaluate the thermal comfort of sows in a free-range system in the Brazilian Savanna, based on behavior observation, availability of shading resources, meteorological and physiological variables. The sows were analyzed in the gestation sector at Água Limpa Farm from University of Brasília; the sows were housed in paddocks of 1000 m² each containing artificial and natural shading structures, where air temperature (T_air, °C), wind speed, relative humidity (R_H, %) and black globe temperatures (T_G, °C) were collected for the environment characterization in 20-min-intervals. From the black globe temperature, the Mean Radiant Temperature (T_MR, °C) and the Radiant Heat Load (R_HL, W m⁻²) were calculated in the sun and under the shade structures. The total short-wave irradiance was calculated through the sum of direct, diffuse and reflected radiations. For the behavioral evaluation, an ethogram was elaborated, taking in consideration where the animals were in the paddocks, body posture, and the activity performed. The physiological variables such as respiratory rate (breaths.min⁻¹), surface and rectal temperatures (°C) were measured during the experiment. The data was statistically analyzed through analysis of variance and frequency analysis. There was a difference at 11a.m., 2 and 3p.m., with values above 40 °C under the shade and above 70 °C in the sun for the T_MR. The preferential choice was for natural shading by the sows, due to the lower T_MR and R_HL throughout the day and resting activity had been predominated. The rectal temperature did not differ between the animals and the days evaluated, respiratory rate varied according to air temperature, and surface temperature only among the evaluated animals. It was concluded that even when there is a greater radiation incidence and meteorological variables above the condition of comfort for sows, they did not express any abnormal behavior that could indicate discomfort.     

Ambient ultraviolet radiation levels in public shade settings

As people become better informed about the harmful effects of prolonged exposure to solar ultraviolet radiation (UVR, 280–400 nm) they will seek the protection of shade, particularly in tropical locations such as Townsville (19° south). Using broad-band radiation sensors for solar ultraviolet-B (280–315 nm), ultraviolet-A (315–400 nm) and daylight (400–800 nm) radiation, the exposure levels were measured in both the horizontal (shaded and unshaded) and vertical (shaded and unshaded) directions. The measurements were conducted at eight locations (shade settings) in Townsville during the period between December 1997 (summer) and May 1998 (beginning of winter). The quality of protection was assessed by the ratio of unshaded to shaded radiation exposure, the UVB/shade protection ratio (UVB-SPR). The UVB-SPR varies considerably between the different shade settings, with a beach umbrella showing the least protection and dense foliage the highest protection. The roof of a house verandah can provide only little protection if the verandah catches the afternoon sun. Increasing cloud cover decreases the UVB-SPR for all settings because of the increase in the diffuse fraction of the radiation. Only one setting provided a UVB-SPR of 15 or higher, as suggested for protective shading against solar UVB radiation. Shade from direct sunlight alone does not provide enough protection against high levels of solar UVR. Apart from the transmission qualities of the shading material, it is the construction of the whole shade setting that determines the exposure levels underneath. A shade structure with enough overhang is recommended so that high levels of scattered radiation do not reach the skin. Received: 26 February 1999 / Accepted: 9 June 1999     

Ammonia nitrogen and inorganic phosphorus excretion by the planktonic rotifers

Two series of experiments were carried out to determine the relation of the rate of phosphorus and nitrogen excretion by the planktonic rotifers to ambient temperature and individual body weights of these animals. The following formulas describing this relation were obtained: E_P=0.0154 W^?1.27 e^0.096T E_N=0.0879 W^?1.01 e^{0.088 T}, where E_P and E_N denote the rate of P and N excretion, respectively, in µg · mg dry wt^?1 · h^?1, W is body weight in µg dry weight, and T is temperature in °C.     

Photoinhibition and recovery in tropical plant species: response to disturbance

Disturbance or rainforest is often followed by mass mortality of understorey seedlings. Transitions of shade grown plants to full sunlight can cause reductions in the efficiency with which light is used in photosynthesis, called photoinhibition. In order to assess the influence of photoinhibition on mortality and growth after rainforest disturbance this study examined photoinhibition in both simulated and real forest disturbances in northern Papua New Guinea. In an experiment simulating rainforest disturbance, exposure of shade-grown plants to full sunlight resulted in abrupt decreases in the chlorophyll fluorescence parameter F _v/F _m that is characteristic of photoinhibition. However, in the well-watered plants used in these experiments there were no fatalities during 3 weeks after exposure to full sunlight. Thus, it is unlikely that photoinhibition, alone, is responsible for seedling fatalities after rainforest disturbances, but more likely that fatalities are due to photoinhibition in conjunction with other environmental stress. There were differences between the response of species to the simulated disturbance that concurred with their preferred habitats. For example, species form the genus Barringtonia, which is commonly found in shaded understorey environments, underwent greater reductions in F _v/F _m and were slower to recover than species that usually inhabit high solar radiation environments. The extent of photoinhibition and the rate of recovery appeared to be dependent on avoidance of direct solar radiation by altering leaf angles and on increasing maximum photosynthetic rates. A field survey of photoinhibition in man-made rainforest gaps corroborated the findings of the simulated disturbance experiment showing that plant species commonly found in shaded environments showed a greater degree of photoinhibition in forest gaps at midday than those species which are classified as species that benefit from gaps or specialist gap inhabitors.     

Size‐dependent effects of daily thermal fluctuations on the growth and size heterogeneity of Nile tilapia Oreochromis niloticus

The growth of Nile tilapia Oreochromis niloticus (0·02–20·00 g) was measured when fed to excess during the hours of light, following their exposure to five thermal regimes fluctuating around the thermal optimum for growth (T_opt = 30° C) over the diel cycle of day (light, L) and night (dark, N), i.e. 27° C(L):33° C(N), 28·5° C(L):31·5° C(N), 30° C(L):30° C(N), 31·5° C(L):28·5° C(N) and 33° C(L):27° C(N) (two replicates per treatment, six weeks' rearing, growth measurements at weekly intervals). A model constructed with a stepwise multiple‐regression analysis accounted for 87·4% of the variation of the specific growth rate (G, % M day^?1) from the variations of wet mass (M), the extent of the thermal fluctuation (F_T) and their interactions, i.e. log₁₀G = 1·7686 ? 0·2136 log₁₀M + 0·0806 [log ₁₀M× log ₁₀ (1 + F_T)] ? 0·0394 [log₁₀M× log ₁₀ (1 + F_T)]². Based on this model, the thermal fluctuation that produces the fastest growth ( ,°C) decreases in a curvilinear way, from 5·1° C at 20 mg to c. 0·7° C at 20 g. Thermal regimes that produce the slowest growth also produce the highest size heterogeneity. Functional hypotheses behind the size‐dependent effects of thermal fluctuations are discussed, together with their implications in natural habitats and aquaculture systems with in different contexts of food availability.     

Are European White Butterflies Aposematic?

It has been suggested that the white coloration of Pieridae butterflies is a warning signal and therefore all white Pieridae could profit from a mimetic resemblance. We tested whether green-veined white (Pieris napi) and orange-tip (Anthocharis cardamines) butterflies benefit from white coloration. We compared their relative acceptability to wild, adult pied flycatchers (Ficedula hypoleuca) by offering live A. cardamines and P. napi together with two non-aposematic butterflies on the tray attached to birds' nesting boxes. Experienced predators equally attacked white and non-white butterflies, and the order of attack among the Pieridae was random. If anything, there was a slight indication that the female A. cardamines was the least favoured prey. Since birds did not avoid white coloration, we compared the palatability of these two species against known palatable and unpalatable butterflies by presenting them to great tits (Parus major). Pieris brassicae, which has been earlier described as unpalatable, was also included in the palatability test. However, there were no significant differences in the palatability of the butterflies to birds, and even P. brassicae was apparently palatable to the great tits. Our results do not unambiguously support the hypothesis that the white coloration of Pieridae would signal unpalatability. Nevertheless, in our last experiment, pied flycatchers often rejected or left untouched free flying P. napi and A. cardamines. This suggests that other features in a more natural situation, such as the agile flight pattern or odours might still make them unprofitable to birds. This revised version was published online in July 2006 with corrections to the Cover Date.     

Low substrate temperature imposes higher limitation to photosynthesis of orange plants as compared to atmospheric chilling

The aim of this study was to evaluate the effects of low air temperature during nocturnal (T_N) and diurnal (T_D) periods as well as the substrate temperature (T_S) on photosynthesis of ‘Valencia’ orange tree grafted on Rangpur lime rootstock. The experiment was carried out in a growth chamber with seven-month-old plants. The plants were exposed to the following temperature regimes: low substrate temperature (LTS, with: T_D = 28°C, T_N = 20°C, T_S = 10°C); low air temperature during night (LT_N, with: T_D = 28°C, T_N = 10°C, T_S = 26°C); low temperature during nighttime and also low substrate temperature (LT_SN, with: T_D = 28°C, T_N = 10°C, T_S = 10°C); low air temperature during both diurnal and nocturnal periods (LT_ND, with: T_D = 17°C, T_N = 10°C, T_S = 26°C); and finally to low air temperature (night and day) and low substrate temperature (LT_SND, with: T_D = 17°C, T_N = 10°C, T_S = 10°C). As reference (control), plants were subjected to T_D = 28°C, T_N = 20°C, and T_S = 26°C. Measurements of leaf gas exchange, photochemical activity and carbohydrate concentrations were performed after six days of exposure to each thermal treatment. Compared to the control, all thermal regimes caused reductions in photosynthesis due to diffusive and metabolic limitations. The photoinhibition was transient in plants exposed to night and substrate low temperatures, whereas it was severe and chronic in plants subjected to chilling during the diurnal period. However, the lowest photosynthesis was observed in plants with low substrate temperature of 10°C (in LT_S, LT_SND and LT_SN treatments), regardless of air temperature. The occurrence of cold night and/or its combination with low substrate temperature caused accumulation of starch in leaves. When considering carbohydrate concentrations in stems and roots, it was not possible to establish a clear response pattern to chilling. In conclusion, the low substrate temperature causes a greater reduction of CO₂ assimilation in citrus plants as compared to the occurrence of low air temperature, being such response a consequence of diffusive and biochemical limitations.     

Photosynthetic characteristics of ornamental passion flowers grown under different light intensities

Responses of leaf gas exchange, fluorescence emission, chlorophyll concentration, and morpho-anatomical features to changes in photosynthetic photon flux density (PPFD) were studied in three wild ornamental species of Passiflora L. to select sun and shade species for landscaping projects. Artificial shade was obtained with different shading nylon nets, under field conditions, which allowed the reduction of 25, 50, and 75% of global radiation, along with a control treatment under full sunlight. For Passiflora morifolia the highest mean values of light-saturated net photosynthetic rate (P _Nmax) and light compensation point (LCP) were observed at 50 and 25% shade, respectively, while the highest values of dark respiration rate (R _D) and apparent quantum yield (α) were observed at 75% shade. For Passiflora suberosa litoralis the highest value of P _max was observed at full sunlight. The highest mean values for P _max, R _D, and LCP for Passiflora palmeri var. sublanceolata were obtained at 25% shade. The highest values of net photosynthetic rate (P _N) for P. morifolia, P. palmeri var. sublanceolata, and P. suberosa litoralis were 21.09, 16.15, and 12.36 μmol(CO₂) m⁻² s⁻¹, observed at 50 and 75% shade and full sunlight, respectively. The values of the minimal chlorophyll fluorescence (F₀) were significantly different in P. suberosa litoralis and P. palmeri var. sublanceolata, increasing with the increase of the irradiance. In contrast, the values of maximum photochemical efficiency of PSII (F_v/F_m) were significantly different only in P. suberosa litoralis, being higher at 75%, progressively reducing with the increase of PPFD levels. The total concentration of chlorophyll (Chl) was higher in shaded plants than in the ones cultivated in full sunlight. On the other hand, the values of Chl a/b ratio were reduced in shaded plants. A significant effect of shade levels on leaf area (LA) and specific leaf area (SLA) was found for the three species, whose highest mean values were observed at 75% shade. The thickness of foliar tissues was significantly higher for the three species at full sunlight and 25% shade. These results suggested that P. morifolia and P. palmeri var. sublanceolata appeared to be adapted to moderate shade conditions. P. suberosa litoralis presented higher plasticity to greater variation of the irradiance levels, while the photoinhibition was one of the limiting factors for this species at full sunlight.     

Shape of leaf photosynthetic electron transport versus temperature response curve is not constant along canopy light gradients in temperate deciduous trees

Responses of foliar light-saturated net assimilation rate (A_max), capacity for photosynthetic electron transport (J_max) and mitochondrial respiration rate (R_d) to long-term canopy light and temperature environment were investigated in a temperate deciduous canopy composed of Populus tremula L. in the upper (17–28 m) and of Tilia cordata Mill. in the lower canopy layer (4–17 m). Climatic measurements indicated that seasonal average daily maximum air temperature (T_max) was 5·5 °C (range 0·7–10·5 °C) higher in the top than in the bottom of the canopy, and strong positive correlations were observed between T_max and seasonal average integrated quantum flux density (Q_int), as well as between seasonal average daily mean temperature and Q_int. Because of changes in leaf dry mass and nitrogen per unit area, A_max, J_max, and R_d scaled positively with Q_int in both species at a common leaf temperature (T). According to J_max versus T response curves and dark chlorophyll fluorescence transients, photosynthetic electron transport was less heat resistant in P. tremula with optimum temperature of J_max, T_opt, of 33·5 ± 0·6 °C than in T. cordata with T_opt of 40·7 ± 0·6 °C. This difference was suggested to manifest evolutionary adaptation of photosynthetic electron transport to cooler environments in P. tremula, the range of which extends farther north than that in T. cordata. Possibly because of acclimation to long-term canopy temperature environment, T_opt was positively related to Q_int in P. tremula, foliage of which was also exposed to higher irradiances and temperatures, but not in T. cordata, in the canopy of which quantum flux densities and temperatures were lower, and gradients in the environmental factors less pronounced. Parallel to changes in T_opt, the activation energy for photosynthetic electron transport decreased with increasing Q_int in P. tremula, indicating that J_max of leaves acclimated to colder environment was more responsive to T in lower temperatures than that of high T acclimated leaves. Similar alterations in the activation energy for mitochondrial respiration rate were also observed, indicating that acclimation to temperature of mitochondrial and chloroplastic electron transport proceeds in a co-ordinated manner, and possibly involves long-term changes in membrane fluidity properties. We conclude that, because of correlations between temperature and light, the shapes of J_max versus T, and R_d versus T response curves vary within tree canopies, and this needs to be taken account in modelling whole canopy photosynthesis.     

Thermoregulation in Malayan sun bears (Helarctos malayanus) and its consequences for in situ conservation

Thermoregulation in Malayan sun bears is not fully understood. Therefore, in this study the effect of meteorological variables on both behavioural and autonomic thermoregulatory mechanisms in sun bears was examined in order to identify temperature thresholds for the activation of various thermoregulatory mechanisms. Infrared thermography was used to non‒invasively determine body surface temperature (T_S) distribution in relation to ambient temperature (T_A) and to determine the thermoneutral zone (TNZ) of sun bears. Thermographic measurements were performed on 10 adult sun bears at T_A between 5 °C and 30 °C in three European zoos. To assess behaviours that contribute to thermoregulation, nine adult sun bears were observed at T_A ranging from 5 °C to 34 °C by instantaneous scan sampling in 60 s intervals for a total of 787 h. Thermographic measurements revealed that the TNZ of sun bears lies between 24 °C and 28 °C and that heat is equally dissipated over the body surface. Behavioural data showed that behaviours related to thermoregulation occurred in advance of energetically costly autonomic mechanisms, and were highly correlated with T_A and solar radiation. While the temperature threshold for the onset of thermoregulatory behaviours below the TNZ lies around 15 °C, which is well below the lower critical temperature (T_LC) assessed by thermography, the onset for behaviours to prevent overheating occurred at 28 °C, which was closer to the estimated upper critical temperature (T_UC) of sun bears. These findings provide useful data on the thermal requirements of sun bears with respect to the species potential to cope with the effects of climate change and deforestation which are occurring in their natural range. Furthermore, these results may have important implications for the care and welfare of bears in captivity and should be taken into consideration, when designing and managing facilities.     

<Emphasis Type="Italic">Pontibacter salisaro</Emphasis> sp. nov., Isolated from a clay tablet solar saltern in Korea

A Gram-negative, aerobic, rod-shaped, and red-pigmented bacterial strain, HMC5104^T, was isolated from a solar saltern, found in Jeungdo, Republic of Korea (34°59′47″N 126°10′02″E). The major fatty acids were summed feature 4 (comprising iso-C_17:1 I and/or anteiso-C_17:1 B; 37.2%), iso-C_15:0 (20.4%), and iso-C_17.0 30H (15.3%). The DNA G+C content was 46.0 mol%. The major isoprenoid quinone was menaquinone-7 (MK-7). A phylogenetic tree based on 16S rRNA gene sequences showed that strain HMC5104^T formed a lineage within the genus Pontibacter, and was closely related to Pontibacter korlensis (95.9%), P. roseus (94.9%), and P. actiniarum (94.3%). Similarities to all other Pontibacter species were between 95.9–93.9%. On the basis of the evidence presented in this study, strain HMC5104^T represents a novel species of the genus Pontibacter, for which the name Pontibacter salisaro sp. nov. is proposed. The type strain is HMC5104^T (=KCTC 22712^T = NBRC 105731^T).