Semi-natural Environment Research Articles

Environmental temperature modulates onset of independent feeding: warmer is sooner.

Individual dams and their litters were observed from Days 14-22 in a seminatural environment consisting of a nestbox attached to a larger, open field in which powdered chow was available. Ambient temperature in the field was either warm (30 degrees C), moderate (21 degrees C), or cold (10 degrees C); nest temperature was always moderate. Behavior was monitored 12 hr/day by time-lapse video recording. The pups' egressions into the field and onset of independent feeding were temperature-related: Weaning was earliest in the warmth and increasingly late with decreasing ambient temperature. Among subjects in the cold condition, there was a positive correlation between duration in the field and duration feeding. Pup growth was unaffected by the temperature regimes. Environmental temperature has emerged as a determinant for early nest egressions and weaning onset.

Social organization and aggression in a group of olfactory bulbectomized male mice

Olfactory bulbectomized and control male CF-1 strain mice were housed in separate, large, seminatural environments over a 30-day observation period. Control mice engaged in vigorous fighting behavior before a dominant animal emerged. The alpha mouse established the floor area as its territory and vigorously attacked all other mice that ventured from the second tier of the enclosure to the floor. Lower ranking mice had numerous body scars, were much less aggressive, and engaged in a variety of nonaggressive social interactions. In contrast, bulbectomized mice did not fight and roamed freely through all areas of the environment. These mice largely ignored one another, engaged in little or no social behavior, and had no body scars. When two anosmic mice came into physical contact, they appeared startled and moved away from one another. These results, together with those of prior studies, indicate that olfaction plays a critical role in virtually all aspects of social behavior in male mice.

Attractiveness of Cabbage Maggot (Diptera: Anthomyiidae) to Entomopathogenic Steinernematid Nematodes

The cabbage maggot, Delia radicum (L.), an important pest of crucifer crops, is a good candidate for control by nematodes, because different parts of its life-cycle occur in the soil. To understand the interaction between nematodes and both eggs and larvae of the cabbage maggot, we examined their attractiveness to the Steinemena carpocapsae All strain in muck soil. We also quantified the ability of some steinernematids to intercept migrant 1st instars before root penetration and to follow larvae into root tunnels in a seminatural environment (soil, plant, host). S. carpocapsae All strain was not attracted by cabbage maggot eggs, whereas they oriented toward newly hatched cabbage maggot larvae. S. carpocapsae All and UK (Biosys 252) strains killed a significant proportion of migrant cabbage maggot larvae before they could penetrate into radish roots. Although most steinernematids tested followed larvae into the radish roots, only S. feltiae (= bibionis ) induced significant infection. Our results indicate that steinernematids have the ability to intercept cabbage maggot 1st in stars and to follow and infect developing cabbage maggot larvae in roots. However, studies must be undertaken to select the best interceptor and tunnel follower nematode species to control the cabbage maggot, as well as to determine the best timing of nematode application.

Influence of effluent discharge on developing seaweed in semi-natural aquatic environments

Influence of effluent discharge on developing seaweed in semi-natural aquatic environments

The ontogeny of littermate preferences in juvenile golden-mantled ground squirrels: effects of rearing and relatedness

The social preferences of captive, juvenile golden-mantled ground squirrels,Spermophilus lateralis, were studied as a first step towards explaining the development of kin-differential behaviour, which occurs frequently in the genusSpermophilus. There groups of young (four litters/group) were reared in the laboratory and then transferred as juveniles at about 36 days of age to an outdoor, semi-natural environment in which social interactions between juveniles were recorded. In group 1, littermates (young born to a common dam) were reared together until behavioural observations began. In groups 2 and 3, pups were cross-fostered between dams shortly after birth to examine how rearing (together or apart) and relatedness (littermates or non-littermates) affected juveniles' social interactions in the semi-natural environment. Social interactions were recorded for a 9-14-day period beginning when juveniles reached about 37 days of age, which coincides with when they would come above ground for the first time in nature. In all three groups, juveniles' social preferences were manifested most clearly in social play. In group 1, littermates (reared together) played together about twice as often as non-littermates (reared apart) on a per pair basis, which suggests that a shared rearing environment influenced the development of social preferences. In groups 2 and 3 in which pups had been cross-fostered, play-bout frequencies were ordered (high to low): littermates reared together>non-littermates reared together>littermates reared apart>non-littermates reared apart, and statistical analysis revealed that both rearing and relatedness contributed to this ordering. The sex of a pair also affected play-bout frequencies (M-M>M-F>F-F) independently of rearing and relatedness. Results fromS. lateralisare compared with studies on other congeners, including parallel work onS. beldingi, in an effort to link interspecific differences in ecology and social organization to differences in the developmental systems that underlie the extent of kin favouritism in ground squirrels.

The release of captive bred snails (Partula taeniata) into a semi-natural environment

A population of zoo bred Partula taeniata was released into a patch of native Polynesian plants in the Palm House at the Royal Botanic Gardens, Kew, London, UK. The released snails were from a colony established from wild-caught snails in 1982, which had been in captive conditions for up to six generations. Monitoring of the snails was continuous and intensive for the first 2 weeks, and at decreasing frequency over the next 15 months. There was high survivorship early on in the release, but once the intensive monitoring ended survivorship became hard to determine due to difficulties in locating snails in the large and complex habitat. However, snails are known to have persisted for at least 15 months, and new individuals have been noted maturing into all developmental stages. The snails exhibited patterns of feeding and microhabitat choice similar to those observed in the wild, despite being reared in a highly artificial environment. The methods and results provide some guidelines for future release trials for this highly endangered group of snails.

Monitoring of large scale contamination of the environment: The learning of Chernobyl

The Chernobyl fallout offered the possibility to test new monitoring methods and better understand the behaviour of radionuclides in natural and semi-natural environments. The research started after the Chernobyl accident confirmed previous knowledge, yet producing new information on the radioecology of forested ecosystems. Biological indicators were used with success to establish a relationship between ground deposition and radioactive transfer to wildlife and to evaluate the biological effects of ionizing radiations at low doses.

Immune and endocrine aspects of social and territorial behavior in male rabbits.

Although there have been some studies of the relation between behavior and mitogen-induced lymphocyte proliferation and immunoglobulin synthesis, few data are available about the effect of behavior on specific lymphokine production. In this study, we describe the effect of social and territorial behaviors on interferon-gamma (IFN-gamma) production by concanavalin A-stimulated peripheral blood mononuclear cells (PBMCs) in pairs of socially naive male rabbits living in a seminatural open-air environment. We also assayed PBMC glucocorticoid receptors (GcRs) and plasma corticosterone (C). Three groups of behaviors were identified: agonistic (Mount and Follow), affiliative (Groom) and territorial (Mark and Dig). Mount was correlated with Follow, while Mark was correlated with Dig. Groom was correlated with all the other behaviors. Groom, Mark, Mount and Follow were all positively correlated with PBMC GcRs. Groom and PBMC GcRs were each negatively correlated with plasma C. The two rabbits in each pair could be distinguished in terms of territorial behavior, since one animal always had a higher score. The animals with the higher level of territorial behavior within the pairs exhibited a significant increase in IFN-gamma production at the end of the experimental period. They also showed a positive correlation between the percentage variations of IFN-gamma production and PBMC GcRs. It is suggested that social factors, especially territorial behavior, affect adrenocortical activity and IFN-gamma production.

Alloparental care and the influence of father presence on juvenile prairie voles, Microtus ochrogaster

Abstract. The influence of fathers on alloparental behaviour of juvenile prairie voles was studied in a semi-natural environment. Juveniles were observed throughout the lactation period either in the presence of both parents and litter or with the mother and litter only. Juveniles remained in the natal nest after the birth of a subsequent litter and displayed alloparental care including huddling over, making contact with, and grooming younger siblings. The presence of fathers influenced the behaviour of juveniles. Juveniles spent more time in the natal nest in contact with younger siblings and less time engaged in passive-alone behaviour (resting on all four feet outside the nest away from other animals) when housed with both parents than with mothers only. This effect was stronger in male juveniles. Developmental changes in alloparental care coinciding with the growth of pups were observed only in the two-parent condition. Younger pups also developed more rapidly when fathers were present.

Persistence and prediction of radiocaesium levels in animals grazing semi-natural environments

In vivo monitoring of radiocaesium levels in a flock of mountain sheep grazing a heather-dominant peatland ecosystem was undertaken over a 3-year period from 1989 to 1991. Highest values were observed during summer and autumn and measurable radiocaesium activities were present throughout the year. Comparably high mean and maximum values recorded in November 1989 are thought to be a result of fungi consumption. Analysis of variance indicated that an increase of 4% occurred in radiocaesium levels in muscle between 1989 and 1990 followed by an overall decrease of 35% between 1990 and 1991. In order to test an existing model to predict radiocaesium levels in muscle from measured activities in faeces, an independent data set was produced. The radiocaesium content of faecal samples collected from the grazing range of a sheep flock was compared with the results of in vivo measurements on the same animals. The correlation over time between the predicted and observed flock mean and maximum values was found to be significant, thereby confirming the value of faeces sampling as an inexpensive and rapid means of assessing the distribution of radiocaesium activities in sheep flocks grazing semi-natural ecosystems.

Chemical methods for reduction of the transfer of radionuclides to farm animals in semi-natural environments

The same chemicals can be used for reduction of radionuclide transfer to animals whether kept on farms or grazing in semi-natural and natural habitats. However, different techniques are required for administration of the active compounds. Dairy ruminants may be treated effectively by inclusion of chemicals in supplemental concentrates. Practical experience gained after the Chernobyl accident has shown that both clay minerals and hexacyanoferrates are effective in preventing high radiocaesium levels in animal products. Chemicals such as bentonite clays and CaCO3, used for reduction of 137Cs and 90Sr transfer respectively, must be fed in hectogram quantities and are only practical for dairy animals in semi-natural ecosystems. Salt licks and sustained release boli with hexacyanoferrates as caesium binders have been developed and used successfully after the Chernobyl accident for ment producing cattle, sheep and reindeer which graze freely for extended periods. Daily doses of 25–300 mg in sheep and 250–2000 mg in cows reduces 137Cs accumulation 2–10-fold. Binders for 90Sr have not been tested in grazing animals. Stable iodine could be provided in salt licks and indwelling rumen boli at rates required to block radioiodine uptake by the thyroid gland. Boli and salt licks are highly cost effective in reducing doses to man when compared to interdiction of food from farm animals.

Effect of environmental enrichment on behaviour, growth and meat quality in the domestic pig

Pigs in a semi-natural environment can spend up to one third of daylight hours in exploratory behaviour (Stolba & Wood-Gush, 1981). It has been suggested that the need for exploration in pigs is as necessary as feeding or sexual behaviour which are generally regarded as endogenous (Van Putten, 1989).This study investigated the effect of enriching the pig's environment on behaviour, growth and meat quality.In a comparative study using 6 groups each of 6 littermates, 3 groups were allocated at birth to an intensive housing system classified as the “barren” (B) environment and 3 groups to an “enriched” (E) environment. The enriched environment had four times more floor space per animal than the barren environment and allowed access to substrates such as peat, straw and shredded paper. Pigs were weaned at 6 weeks of age and pen size was increased at 6 and 12 weeks of age on both treatments. In both environments the pigs were fed ad libitum and had a continuous water supply. The behaviour of 2 focal animals in each group was observed for 10 minutes twice weekly between 1300 and 1800 hours throughout the 18 week life span of the animals. At 6 week intervals 24 hour time lapse video recordings were made to examine overall activity patterns.

Long-term heartrate responses to social stress in wild European rabbits: Predominant effect of rank position

The long-term mean heartrates of wild European rabbits living in a seminatural environment have been studied based on more than 1500 days of radiotelemetrical heartrate recordings. Significant differences between the heartrate levels of dominant and subordinate individuals have been found. Subordinate rabbits show chronically elevated heartrate that cannot be explained by limited access to burrow shelter or by the cumulative effect of heartrate reactions during aggressive encounters. If a subordinate rabbit achieves a dominant position, its heartrate is gradually adjusted to the lower level characteristic of dominant individuals. These results are discussed with respect to the consequences of dominance in species with different social systems.

Interactions of Mothers with Partners of Different Sexes in Meadow Voles and Prairie Voles

The behavior of lactating female meadow voles ( Microtus pennsylvanicus ) and prairie voles (M. ochrogaster ) housed with partners of either sex was examined in an indoor, seminatural environment. Females were observed either alone, in the presence of the breeding male, or in the presence of a familiar, virgin female (sibling). Although there was no effect of partner condition on maternal behavior in either species, interactions between mothers and partners varied between species. Meadow-vole mothers spent less time in social interaction than prairie-vole mothers, and their interactions primarily were with female partners. In contrast, prairie-vole mothers primarily interacted with the male with whom they shared a nest and kept female siblings from entering the natal nest until pups were close to weaning age. The differential response of female prairie and meadow voles to partners of different sex is consistent with their winter social organizations.

Dose-dependent effect of testosterone on the induction of eclipse coloration in castrated wild mallard drakes (Anas platyrhynchos L.)

Four groups of adult wild mallard drakes that had been previously castrated were injected daily with 5, 1, or 0.2 mg testosterone dissolved in propanediol or with the vehicle alone. The injections started on February 29 and continued for 64 days during the natural breeding season of the species. The birds were kept in outdoor aviaries in a seminatural environment in Kiel (54°N). By the end of the postnuptial molt in mid-July the groups differed markedly in coloration. The vehicle-injected control group had regained an almost typical nuptial plumage, whereas the castrates that had received the highest daily dose of testosterone exhibited an almost complete eclipse plumage. The two other groups showed an intermediate pattern, with about 40% eclipse coloration in the group injected with 1 mg testosterone/day and about 10% eclipse coloration in the group that had received 0.2 mg testosterone/day. The possible role of the aromatization of testosterone to estrogens in the induction of the eclipse coloration is discussed.

Effects of salinity on growth of Baltic and AtlanticFucus vesiculosus

Vegetative apices of intertidal Atlantic and permanently sublittoral, brackish water, Baltic Fucus vesiculosus were cultured in a salinity range (1·5–45 ppt) in the laboratory. Tank experiments with running Baltic sea-water were also conducted under summer (10–20°C) and autumn (7–10°C) temperature ranges. Both populations were able to grow in a wide range of salinity in laboratory culture. The Atlantic population showed better growth in higher salinities and virtually no growth in 1·5 ppt, in which it died after 7 weeks. In contrast the Baltic plants grew better in the lower range of salinity. Baltic material took nearly 4 weeks to recover from upshock in salinities 34 and 45 ppt, and showed 10–15% loss of tissue weight during the first two weeks. Growth then started, but in the highest salinity (45 ppt) growth was negligible. When cultured in a semi-natural Baltic environment, in a tank experiment, Atlantic plants could not survive whereas Baltic plants showed vigorous growth. The combination of continuo...

Analysis of colour infrared aerial photography and SPOT satellite data for monitoring land cover change of a heathland region of the Causse du Larzac (Massif Central, France)

Abstract Stereoscopic interpretation of colour infrared (CIR) aerial photographs and analysis of SPOT multispectral (XS) data offer alternative methods for the documentation of land cover change of the Causse du Larzac, of a heathland region in the southern part of the Massif Central, France. Discussion of multitem-poral classification results leads to an advanced understanding of the value of visual and/or computer-related image interpretation of seminatural environments. Analysis of in situ measurements of spectral reflectance properties of classified land cover types completes the investigation of remotely sensed heathland monitoring.

Transfer of Radionuclides in Natural and Semi‐Natural Environments

Journal of Environmental QualityVolume 21, Issue 1 p. 154-155 Book Review Transfer of Radionuclides in Natural and Semi-Natural Environments Edited by G. Desmet, P. Nassimbeni, and M. Belli, Elsevier Applied Science, 655 Avenue of the Americas, New York, NY 10010. 1990. 693 p. ISBN 1-85166-539-0 Stephen C. Sheppard, Environmental Science Branch, AECL Research, Pinawa, Manitoba, Canada, R0E 1L0Search for more papers by this author Stephen C. Sheppard, Environmental Science Branch, AECL Research, Pinawa, Manitoba, Canada, R0E 1L0Search for more papers by this author First published: 01 January 1992 https://doi.org/10.2134/jeq1992.00472425002100010032xAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume21, Issue1January‐March 1992Pages 154-155 RelatedInformation

Vocal communication as a function of differential rearing experiences inPan paniscus: A preliminary report

There is little evidence of vocal learning in nonhuman primates despite the well-documented abilities found in avian species. We describe the vocal repertoire of five bonobos (Pan paniscus), four of which live in a seminatural environment. The fifth subject, Kanzi, has been reared with humans during the course of language training. The data indicated that the four bonobos living in a seminatural environment exhibit a variety of species-typical vocalizations. In addition to producing all the species-typical vocalization, Kanzi produced four structurally unique vocalizations that were not heard among the other subjects. These data suggest that Kanzi has learned vocalizations that are novel due to his unique rearing experience. Discussion is focused on the flexibility of vocal communication and vocal comprehension inPan paniscus.

Self-directed behaviour and hippocampal electrical activity in rabbits living in a semi-natural environment

Rabbits living in a semi-natural environment show a variety of behavioural elements related to voluntary or automatic movements. The aim of the present experiment was to study the hippocampal electrical correlates of self-directed activities occurring during spontaneous behaviour and emotional responses (the presence of a second rabbit of the same sex: intruder). Behaviour was divided into two broad categories. One included autocleaning elements such as scratching, shaking, washing and self-grooming. The other was characterized by consummatory activities: eating and drinking. Hippocampal activity was recorded by telemetry and the EEG periods related to specific behavioural elements were selected and analyzed. The electrical parameters were different for the various behavioural elements, for example rhythmic and irregular EEG patterns were recorded in different percentages during autocleaning and consummatory activities. Differences were also observed in the frequency peak distributions of power spectra. Confrontations influenced the occurrence of self directed behavioural elements and modified the pattern and frequency of hippocampal EEG during autocleaning activities. Results show that environmental variations can affect automatic behaviours and influence the mechanisms of hippocampal function.