Fulmarus glacialis in sachsen

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Hearing and communication in blue monkeys (Cercopithecus mitis)

Hearing and vocal communication in blue monkeys (Cercopithecus mitis) was studied within an ecological context. Field measurements of the acoustical characteristics of the blue monkey's natural habitat were conducted in the Kibale forest (Uganda) and in Kakamega forest (Kenya). Measurements of background noise levels indicated that vocal communication pitched in the 100–1000-Hz frequency band would be relatively unimpeded by disruptive background noises. Furthermore, measurements of the propagation rate of audio signals indicated that calls pitched in the 125–200-Hz region penetrated the forest with minimal decrement in amplitude. Tests of the blue monkey's acoustic sensitivyty and range of hearing were conducted in the laboratory with standard audiometric procedures. Hearing in the blue monkey was characterized by a U-shaped function, with maximum sensitivity of about 5 dB SPL spanning a four-octave range from 1 to 16 kHz. The hearing of blue monkeys was superior to human hearing for tones below 500 Hz and above 8 kHz in frequency. A comparative analysis of primate hearing indicated that the blue monkey was approximately 18 dB more sensitive to low-frequency tones than the comparably sized, semi-terrestrial rhesus monkey (Macaca mulatta). Furthermore, blue monkeys exhibit phonatory specializations for vocal production in this relatively unused, low-frequency band of 125–200 Hz. These specializations for low-frequency vocal production and low-frequency hearing collectively act to increase the effective distance of long-range acoustic communication in the forest canopy.     

Prey selection and the impact of the starfish Marthasterias glacialis (L.) and other predators on the mussel Choromytilus Meridionalis (Krauss)

The diet of the starfish, Marthasterias glacialis (L.), consists of a variety of mollusc species, as well as ascidians and barnacles. Starfish densities are maximal where mussels, Choromytilus meridionalis (Krauss), are abundant and in such areas mussels form the bulk of the diet. Laboratory feeding experiments indicate that Marthasterias glacialis select mussels of particular sizes and that the length of prey taken is an increasing function of predator arm length. The time taken to consume each mussel is determined by the ratio of shell length to starfish size. The number of mussels consumed per day increases only slightly with starfish size, but because the prey taken increase in size, energy consumption is maintained at a relatively consistent 1% of predator body energy per day. Using prey selection and feeding rate data for different sized starfish, predictive three dimensional predation surfaces are developed for a natural starfish population feeding on either one or two cohort Choromytilus meridionalis populations. The models indicate that predatory effort should be concentrated on the smallest mussels when a single adult cohort is present, but on recruiting mussels just above the minimum prey size limit where two cohorts are present. Other major predators of mussels, the rock lobster, Jasus lalandii (Milne Edwards), and the whelk, Natica tecta Anton, appear to select similar size-ranges of prey to starfish, despite their differing body forms and feeding methods. Since the juveniles of all three predators can only take small mussels, predator recruitment may well depend upon the successful settlement of strong mussel cohorts. Evidence for such entrainment of predator cohorts to settlements of mussels is presented.     

Aggressive and maternal activities of female southern elephant seals (Mirounga leonina)

The aggressive and maternal behaviours of 44 individually marked female southern elephant seals, Mirounga leonina, were studied at South Georgia. Evidence of dominance and subordination could be determined in only 29% of 1315 encounters, but dominance-subordination relationships were observed in 49% of known cow dyads. Status was not necessarily size- or age-related, but most young, small cows were of low status. High-status cows reared larger pups which were bitten less frequently than pups of low-status cows. Orphaned pups were bitten at least three times as frequently as pups with mothers. Cows with pups initiated more interactions than pregnant cows, and were dominant more frequently. Older cows responded to their newborn pup more rapidly and intensively than did younger cows and this difference can be important in crowded breeding assemblies. Cow and pup behaviour in M. leonina at South Georgia is compared with that of M. angustirostris in California. The main differences are thought to relate to differences in population density.     

Commensal auditory communication in two species of Neoconocephalus (Orthoptera)

Auditory communication in Neoconcephalus ensiger and Neoconocephalus robustus, two stridulating tettigoniids that inhabit the same geographical area, was examined to determine how these two species interact. Computer and electrophysiological techniques were used to analyze sound production and reception. Although similar in appearance, the males of these species produce easily distinguishable acoustic communication signals (call songs) that serve to attract conspecific females. Both wave form and spectral analyses were done on selected segments of the species-specific call songs by using discrete Fourier transform techniques. Sound production and reception capacities were measured by octave-band analyzers and extracellular electrode techniques. The results show that each of these species has a distinct, primary carrier frequency band. Secondly, the log magnitude spectra revealed a significant secondary component in the call song of N. robustus which corresponds to the primary energy band in the call song of N. ensiger. This overlap in acoustic signals and other findings suggest that males of N. ensiger might use the louder stridulation of the more metabolically active N. robustus to attract conspecific females over great distances. N. ensiger males have a sound production capacity like N. robustus, but conserve energy for soft, near-field signaling. The audiogram representing sensitivity of the tympano-receptor in the foreleg showed sound reception to be matched precisely with sound production curves.     

Carotenoids of the lily beetle (Lilioceris lilii) and of its food plant (Lilium hansonii)

Six carotenoids were identified in the leaves of Lilium hansonii, and of these, only two, namely β-carotene and 5,6-monoepoxy-β-carotene were found in the lily beetle. Further, 4-OH, 4,4¹-di-OH, and keto-carotenoids were found either in the larvae or in the adults of the beetle. As these were not found in its food plant, the insect must have been able to convert ingested carotenoids into these compounds. The presence of isozeaxanthin and absence of cantaxanthin in the larvae while both compounds were found in the adults suggest a precursor-product relationship. This is in agreement with possible pathways leading to the formation of keto-carotenoids.     

Incubation scheduling by Northern Fulmars ( Fulmarus glacialis ) in the Canadian High Arctic

Northern Fulmars (Fulmarus glacialis) are a ubiquitous seabird of the North Atlantic and North Pacific oceans that breed in colonies surrounded by markedly different marine environmental conditions. I have studied the incubation behavior of fulmars at a remote colony in the Canadian High Arctic, where the birds had to cross 200 km of sea-ice during the early incubation period to reach feeding areas. These fulmars completed incubation in fewer shifts and had a longer mean incubation shift duration (5.3 days) than their counterparts breeding in the Boreal oceanographic zone. In particular, the mean duration of the first incubation shift by males in successful pairs (10.3 days) was 2 days longer than that for males in unsuccessful pairs and was longer than that reported at any other colony. This exceptionally long shift by the male may be required at this site to give females enough time to recoup energetic reserves after egg-laying, at a time when marine productivity in the Arctic is still seasonably low.     

The function of colourful facial bands in mangrove crab (Perisesarma) communication

Bright colours are a key visual signal in many animal communication systems. Here we examine the function of the blue-green facial bands found in two species of mangrove crabs, Perisesarma eumolpe (De Man) and P. indiarum (Tweedie). Food (mangrove leaves) deprivation and re-feeding experiments demonstrated that facial band brightness and saturation changed significantly with nutritional status. These results suggest that the colours are diet-derived and could be carotenoid-based. Manipulation of the facial bands had significant effects on inter-crab behaviour. When P. indiarum and P. eumolpe males were given a choice between a female with its facial band blacked out and a similar-sized control female with natural colour, they consistently chose the latter. In a resource holding potential (RHP) experiment, male crabs defending burrows responded differently to male con-specific intruders with blacked out facial bands compared to non-blacked out controls. Together, the results show that brightly coloured facial bands in P. eumolpe and P. indiarum are important for communication; either as a way to identify conspecifics, or to convey nutritional status and hence physical quality.     

Rats (Rattus norvegicus) and pigeons (Columbia livia) are sensitive to the distance to food,but only rats request more food when distance increases

Three experiments investigated foraging by rats and pigeons. In Experiment 1, each response on a manipulandum delivered food to a cup, with the distance between the manipulandum and the cup varying across conditions. The number of responses made before traveling to collect and eat the food increased with distance for rats, but not for pigeons. In Experiment 2, two manipulanda were placed at different distances from a fixed food source; both pigeons and rats preferentially used the manipulandum closest to the food source. Experiment 3 was a systematic replication of Experiment 1 with pigeons. In different conditions, each peck on the left key increased the upcoming hopper duration by 0.5, 1.5 or 2.5 s. Completing a ratio requirement on the right key of 1, 4, 8, 16 or 32 pecks, depending on the condition, then produced the food hopper for a duration that depended on the number of prior left pecks. As the ratio requirement increased on the right key, pigeons responded more on the left key and earned more food. Overall, the results replicate previous research, underlining similarities and differences between these species. The results are discussed in terms of optimal foraging, reinforcer sensitivity and delay discounting.     

Learning and owner-stranger effects on interspecific communication in domestic dogs (Canis familiaris)

Domestic dogs are very successful at following human cues like gazing or pointing to find hidden food in an object choice task. They solve this kind of situation at their first attempts and from early stages of their development and perform better than wolves. Most of the authors proposed that these abilities are a domestication product, and independent from learning processes. There are few systematic studies on the effects of learning on dogs’ communicative skills. We aim to evaluate the effect of extinction and reversal learning procedures on the use of the pointing gesture in an object choice task. The results showed that dogs stopped following the pointing cue in the extinction and that they learned to choose the not pointed container in the reversal learning. Results suggest that instrumental learning plays an important role in interspecific communication mechanisms between humans and dogs. In both experiments for half of the subjects the pointer was the owner and for the rest was a stranger. A differential effect was found: extinction was slower but reversal learning was faster when the owner gave the cue. This data indicates that the relationship of the dog with the person who emits the cue influences performance.     

Chemical communication during swarm emigration in the social wasp Polybia sericea (Olivier)

Communication during swarming was studied in the social wasp Polybia sericea in Brazil. After the adult population (swarm) evacuates following destruction of the nest, it forms a temporary (0.5- to 2-day) cluster on nearby vegetation and then emigrates to a new nest site. During both phases many adults drag the gaster over leaves and other substrates around the cluster and along the emigration route. The odour left on these objects is identical to that of the copious secretion of an exocrine gland opening at the base of the fifth (penultimate) sternite of the gaster. Following emigration the deposit of secretion in many individuals is depleted and shows signs of disturbance. Experimental evidence is presented to show that the swarm, if chased from its cluster site, reorients to it by means of the scent marks alone. It is further demonstrated that the swarm is guided to its new nest site by the trail of scent marks along the emigration route.     

DNA profile of a sixteenth century western North Atlantic right whale (Eubalaena glacialis)

Low levels of genetic variability identified within the North Atlantic right whale (Eubalaena glacialis), when compared to the Southern right whale (E. australis) and other large whales, have been suggested to result from population reductions due to whaling. Previous genetic analysis of 218 whale bones from sixteenth century Basque whaling sites in the western North Atlantic revealed only a single right whale bone. We determined the genotypes of 27 microsatellite loci using DNA isolated from this bone. All alleles from the historic specimen occur in the extant western North Atlantic population and both the probability of identity of the specimen and the number of heterozygous loci are similar to that in the extant population. Assessments of how genetically different the historical population might have been suggest genetic characteristics have not changed substantially over four centuries of whaling.     

Lavandula angustifolia essential oil as a novel and promising natural candidate for tick (Rhipicephalus (Boophilus) annulatus) control

Lavandula angustifolia is a well known herbal medicine with a variety of useful properties, including its acaricidal effect. This experiment was carried out to study the bioacaricidal activity of L. angustifolia essential oil (EO) against engorged Rhipicephalus (Boophilus) annulatus (Acari; Ixodidae) females. For this purpose six serial concentrations (0.5, 1.0, 2.0, 4.0, 6.0 and 8.0% w/v) of L. angustifolia EO were used. There was considerable mortality in concentrations more than 4.0% although there were no differences between 6.0 and 8.0% in all measured criteria. The mortality rate 24 h after inoculation was 73.26 and 100% in groups treated with 4.0 and 8.0% EO, respectively. Lavender EO also reduced tick egg weight in a concentration-dependent manner. The amount of eggs produced varied from 0.12 g (at 0.5% EO) to 0.00 g (at 8.0% EO) but did not differ statistically from the control. L. angustifolia EO caused 100% failure in egg laying at 6.0 and 8.0% whereas this value in the control group was zero. A positive correlation between L. angustifolia EO concentration and tick control, assessed by relative mortality rate and egg-laying weight, was observed by the EO LC/EC₅₀, which, when calculated using the Probit test, was 2.76-fold higher than the control. Lavender is a promising acaricidal against R. (B.) annulatusin vitro.     

Chemical communication in Cavia: Responses of wild (C. aperea), domestic (C. porcellus) and F1 males to urine

Urine preferences of wild (Cavia aperea), domestic (C. porcellus), and F₁ adult male guinea pigs were investigated. Males of all three types preferred female urine to male urine regardless of donor type. When given a choice between female urine of each type, males preferred conspecific urine. In choices between male urine of the three types, a conspecific preference was evident for wild and domestic but not f₁ subjects. These data indicate that a loss of distinctive male and female odours has not occurred as a result of domestication. However, the urine odours of wild and domestic types have diverged. The possible effects of previous individual experience on the preferential response is discussed.     

Preference for mirror-image stimulation in finches (Passer domesticus domesticus) and parakeets (Melopsittacus undulatus)

When given a continuous choice both finches and parakeets were observed to spend appreciably more time in front of their own reflection in a mirror than in front of another bird, food, or a blank piece of cardboard. The preference for mirrors not only persisted over days, but showed a tendency to increase in both species. An attempt to explain these data in terms of what are considered to be unique psychological properties of mirror-image stimulation was presented.     

Preference for structured environment in zebrafish (Danio rerio) and checker barbs (Puntius oligolepis)

Information about the welfare and husbandry of pet and laboratory fish is scarce although millions of fish are sold in pet shops and used in laboratory research every year. Inadequate housing conditions can cause behavioural problems also in fish since they are complex animals with sophisticated behaviour. In this study, we investigated the influence of environmental complexity on compartment preference and behaviour in zebrafish (Danio rerio) and checker barbs (Puntius oligolepis). For the preference test, large aquaria were divided by two semi-transparent walls of Plexiglas into an empty compartment, a structured compartment enriched with plants and clay pots, and a smaller compartment in-between, where food was provided. For observation, the empty and structured compartments were divided into six zones of similar size by defining three vertical layers and two horizontal areas (back vs. front area). Seven groups of six to nine zebrafish and seven groups of seven or eight checker barbs were observed on four days each (within a time period of ten days) to assess compartment use and activity, and to assess behavioural diversity and use of zones within compartments. Both zebrafish and checker barbs showed a significant preference for the structured compartment. Nevertheless, in neither species did behavioural diversity differ between the empty and structured compartment. Zebrafish used all zones in both compartments to the same extent. Checker barbs, however, used the structured compartment more evenly than the empty compartment, where they mainly used the lower and middle zones. These results suggest that zebrafish and checker barbs have a preference for complex environments. Furthermore, they indicate that the behavioural and ecological needs of fish may vary depending on species, and recommendations for husbandry should be specified at species level.     

Cortinarius sect. Brunnei (Basidiomycota, Agaricales) in North Europe

The section Brunnei was extensively studied based on material from North Europe. To stabilise the nomenclature we studied the relevant types of taxa included in this section. Phylogenetic relationships and species limits were investigated using rDNA ITS sequences and the results were compared with the morphological data. We recognised 11 species: Cortinarius brunneus, C. clarobrunneus comb. nov., C. coleoptera, C. ectypus, C. gentilis, C. glandicolor (neotypified), C. pseudorubricosus, and four species described as new C. caesiobrunneus, C. albogaudis, C. carabus, and C. cicindela. They are described here and their taxonomy, ecology, distribution, and relationships are discussed. In addition, a key to species of the section Brunnei is provided. A total of 77 new sequences of 11 species are published including nine type sequences. Also the taxonomic assignments of sequences in the public databases belonging to the section Brunnei are revised.     

Female-offspring communication in a Taiwanese tree frog, Chirixalus eiffingeri (Anura: Rhacophoridae)

We assessed the roles of visual and olfactory cues in female-tadpole communication inChirixalus eiffingeri . The mean cumulative time that at least one tadpole was active or begged for food was significantly longer when a female C. eiffingeri was present than when a plastic frog was introduced and when no frog was present. Tadpoles did not respond visually to a female frog physically separated from them by transparent Plexiglas. However, tadpoles were more active in water conditioned by female frogs than in unconditioned water. Tadpole activity was further elevated by water conditioned by a female frog and tadpoles. Tadpoles were more active in water conditioned by male frogs than in unconditioned water, but water conditioned by a male frog and tadpoles did not further elevate tadpole activity. Thus, water conditioned by adults of either sex contains substances that increase tadpole activity, but only females show a synergistic effect with conditioning by tadpoles. Copyright 2002 Published by Elsevier Science Ltd on behalf of The Association for the Study of Animal Behaviour     

Demand for sucrose in the genetically obese Zucker (fa/fa) rat

Obese Zucker rats (fa/fa) eat more food than lean controls in free-feeding conditions, which strongly influences their phenotypic expression. Few studies, however, characterize their food consumption in environments that are more representative of foraging conditions, e.g., how effort plays a role in food procurement. This study examined the reinforcing efficacy of sucrose in obese Zucker rats by varying the responses required to obtain single sucrose pellets. Male Zucker rats (15 lean, 14 obese) lever-pressed under eight fixed ratio (FR) schedules of sucrose reinforcement, in which the number of lever-presses required to gain access to a single sucrose pellet varied from 1 to 300. Linear and exponential demand equations, which characterize the value of a reinforcer by its sensitivity to price (FR), were fit to the number of food reinforcers and responses made. Free food consumption was also examined. Obese Zuckers, compared to leans, consumed more food under free-feeding conditions. Moreover, they had higher levels of consumption and response output, but only at low FR values. Both groups were equally sensitive to price increases at higher FR values. This suggests that environmental conditions may interact with genes in the expression of food reinforcer efficacy.