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1.
Educational field trips are common practice in environmental education and education for sustainable development, well recognised by researchers for their potential to achieve cognitive and affective educational outcomes. One of the factors that influences learning during field trips is their novelty. The current study focuses on the interplay between novelty, preparation and environmental learning outcomes of 5th and 6th grade students during a typical field trip in Flanders. Our dependent variables are Inclusion of Nature in the Self, the two major ecological values Preservation and Utilisation and ecosystem knowledge. The sample includes 484 students (10–12 years old) and their 24 teachers. Key questions addressed are: (1) What is learned during the field trip? (2) What is the level of novelty for students during a field trip? (3) How does the novelty effect relate to learning? Results show that participation in the field trip leads to a substantial increase in ecosystem knowledge, but fails in reaching the affective goals set out by the field trip organisers. Our results furthermore provide support for the hypothesised non-linear relationship between novelty and knowledge gain, showing that while a little novelty is positive, too much novelty can stand in the way of learning.  相似文献   

2.
During the chick-rearing period, little auks Alle alle adopt a bimodal foraging strategy, alternating long trips with several short ones. It has been postulated that they reach more remote areas during long feeding trips than during short ones. However, the range of their foraging flights has never actually been measured. The aims of this study were to find the exact location of the little auk feeding grounds and to investigate whether they reach remote areas during long foraging trips using miniature GPS and temperature loggers. The study was conducted in 2009 in Magdalenefjorden (79°34′N, 11°04′E), one of the main breeding grounds of little auks on Spitsbergen. The temperature logger records indicated that during short trips, little auks visit warmer waters (situated close to the colony) than during long ones. The tracks of two GPS-equipped birds indicated that during long trips little auks foraged in the distant, food-abundant marginal sea ice zone, at least 100 km away from the colony. During long trips, birds make several stops at sea, perhaps sampling the foraging area with respect to prey distribution. Since food conditions near the studied colony are usually suboptimal, little auks may be exploiting distant feeding areas to compensate for the poorer-quality food available at nearby foraging grounds. The extended duration of long foraging trips may enable birds to collect food for chicks on food-abundant, remote foraging grounds as well as acquire, process and excrete food needed for self-maintenance, reducing the costs of flight to the colony.  相似文献   

3.
We describe the features of waters where seabirds were feeding by sampling vertical water temperature profiles with data loggers mounted on five Brünnich's Guillemots in Svalbard, Norway. The guillemots foraged in a cold water (−0.5–0.5°C SST (sea surface temperature)) by making 1.8 dive bouts in short trips (32–257 min duration) as well as in moderate (0.5–2.0°C SST) and warm waters (2.5–4.0°C SST) by making 6.0 dive bouts during long trips (411–688 min duration). Judging from outbound flying time (15.7–24.4 min), time between dive bouts (23.9–43.3 min) and water types, the birds probably fed in fjord or coastal waters during short trips and in both coastal and offshore waters during long trips. Water temperature and diving behaviour can be simultaneously recorded by small data loggers, which therefore will provide useful information on marine features and foraging activity of top predators.  相似文献   

4.
Although medical students on clinical ward rotations receive a large part of their education from house officers, very often house officers themselves have had little formal preparation as teachers. Because students and teachers work closely together under special conditions, unique educational situations are created where much more than factual information is conveyed. Although some house officers are "natural" teachers, others find such activities uncomfortable or burdensome. Most people, however, can be taught to be effective teachers, and preparation for teaching and teaching itself are beneficial for house officers and their patients as well as their students. House officers who teach enjoy the rewards that all teachers know as well as several others which are particular to the setting in which they teach. Mechanisms are suggested to maintain and develop interest in house staff teaching.  相似文献   

5.
We studied several aspects of the foraging ecology of fulmars rearing young chicks on Bjørnøya. To determine precisely the duration of foraging trips during the brooding period, we used an automated logging system that recorded the presence of fulmars fitted with transponders. We also tracked, with satellite transmitters, four parent fulmars during the brooding period, and two after the chick had been left alone. When brooding the chick, fulmars appeared to alternate very rapidly on the nest, with foraging trips lasting on average 8?h. This period appeared constraining for the birds since parents lost mass. The growth of chicks was dependent on the ability of the female (and not the male) to do short foraging trips. At this time birds are foraging at an average distance of 60?km from the colony, with birds concentrating on the shelf around Bjørnøya. They did not return from one trip to the next to the same foraging area. As the season progressed and the chicks were left alone on the nest, parents increased the duration and maximum range of foraging trips as well as the distance covered. However, they still perform a succession of relatively short foraging trips to the east of the Bjørnøya shelf but they interspersed these short trips with longer foraging trips. One bird returned twice to the same site along the Norwegian coast 570?km from Bjørnøya, the other foraged at 580?km in the mid-Barents Sea. Average flight speed including time spent on the water was 28?km/h and reached 70?km/h during bouts of more than 1?h when the bird was probably continuously in flight.  相似文献   

6.
This report, the second in a series on field trips to Kenya, Africa, provides baseline information on the microbiology and parasitology of the baboon (Papio sp.) as this animal exists in its native habitat. Specimens were collected for bacteriology, mycology, parasitology, pathology, and virology as well as for a number of ancillary biomedical purposes from three major geographic areas in Kenya. Preliminary compilations of data and information obtained during the course of field studies indicate varying relationships between the presence of infective agents and parasites and the areas from which baboons were captured. It has been shown clearly that ecologic factors influence the physical appearance of the animal as well as their microbial flora and parasite fauna. The close spatial relationship of the baboon to man as well as to other animals, both wild and domestic, very probably accounts for an interchange of organisms and exerts influences on potentials for transmission and propagation of parasites. Data collected from such field studies, when integrated with those obtained as a result of longitudinal studies on baboons maintained in captivity over a five year period, plus various taxonomic and basic biomedical considerations, will be of paramount importance for establishing the baboon as a model for studies on human diseases.  相似文献   

7.
The potential use of IT in secondary biology teaching is enormous, although it is a huge undertaking and fairly daunting to newcomers. Computer learning packages and the web can offer a variety of opportunities for learning, ranging from non-interactive content provision to highly interactive student-centred learning experiences. The learning materials in use in New South Wales (NSW) schools include information web sites, computer learning packages as tutorial or revision material, computer learning packages made by the students, virtual field trips, simulations, and virtual laboratories. In addition, students and teachers are using the web for communicating amongst themselves via email, newsgroups and discussion lists, videoconferencing for both local and global communications, and telecollaborative projects. This article will focus on materials used in student learning, and on the forms of electronic communication in use within the school system. A list of resources is provided.  相似文献   

8.
Thomas A. Zanoni 《Brittonia》1980,32(4):551-571
Otto Kuntze (1843–1907) is renowned for hisRevisio generum plantarum in which he changed thousands of plant names in accordance with his revision of the 1867 Paris Code of Botanical Nomenclature. His contributions to plant taxonomy, based on his world-wide collecting trips, and his monographs are not as well known. A short biographical sketch and bibliography of Kuntze’s natural history and plant taxonomy publications are included with detailed enumeration of localities and dates for trips around the world in 1874–1876 and 1904, to southern U.S.S.R. in 1886, to the Canary Islands and Madeira in 1887–1888, to South America in 1891–1893 and to southern Africa in 1894. Herbaria housing Kuntze specimens are cited. The majority of the type specimens are at the New York Botanical Garden.  相似文献   

9.
Boyd  I. L. 《Behavioral ecology》1999,10(2):198-208
This study examined three competing hypotheses to explain howlactating Antarctic fur seals (Arctocephalus gazella) respondto changes in the level of resource availability. Antarcticfur seals have episodic bouts of suckling (1-3 days), alternatingwith foraging trips (3-10 days). Foraging time budgets variedsignificantly (p <.001) among 8 consecutive years at BirdIsland, South Georgia. Foraging trip duration increased during periodsof relative food shortage. Time spent ashore was more consistentamong years than foraging trip duration but declined duringa year of particularly low food availability. In 4 of the 8years, there was a significant positive correlation betweentime spent ashore and foraging trip duration. In the other years,the relationship was close to statistical significance. Energydelivery to pups during suckling bouts followed an asymptoticpower function. Energy gain during foraging trips was estimatedfrom diving behavior, which suggested that the energy gain functionwas linear. Distance traveled during foraging trips was correlatedwith foraging trip duration, and long foraging trips were associatedwith reduced foraging intensity. There was support for the hypothesisthat lactating Antarctic fur seals compensate for reduced resources byincreasing the foraging trip duration rather than working harderand increasing their energy expenditure. However, there wasmost support for the hypothesis that lactating Antarctic furseals adjust time spent ashore as well as foraging trip duration,possibly to maximize the delivery of food to their offspring.Lactation appears to impose constraints on provisioning of offspringthat differ from those of seabirds foraging in the same environment andoften on the same prey.  相似文献   

10.
Parasites, by altering the nutritional and energetic state of their hosts, can significantly alter their foraging behaviour. In honeybees, an infection with Nosema ceranae has been shown to lower the energetic state of individual bees, bringing about changes in behaviours associated with foraging. Comparing the foraging trip times, hive times in between trips, and the crop contents of uninfected and infected foragers as they depart on foraging trips and return from them, this study examined how any differences in these variables influence alternative foraging currencies. The results show that infected bees take longer foraging trips, spend shorter time in the hive between successive trips and bring back less sugar from each trip. These changes have a stronger adverse effect on their efficiency of energetic gain as compared with their rate of energetic gain, which has important implications for individual and colony life history.  相似文献   

11.
Cover illustration: Polymer and Textile Biotech. Polymer biotechnology has led to highly functional materials with wideranging applications from textiles to medicine. This includes protective clothing, which could for example be used for future space trips, as well as for tissue engineering. This special issue of BTJ, edited by Georg Guebitz, Graz University of Technology, Austria (co-edited by Giuliano Freddi and Artur Cavaco-Paulo) provides a broad overview of novel biotechnological approaches for processing of materials and textiles. Cover image: Astronaut © Lasse Kristensen – Fotolia.com  相似文献   

12.
A new type of bird-borne data logger, which stores data from flight and depth sensors at pre-set intervals, was used to investigate the foraging pattern and diving behaviour of chick-rearing Razorbills Alca torda breeding on the islet of Græsholmen (central Baltic Sea, Denmark). The instruments recorded all relevant events in the 35 foraging trips accomplished by six different individual birds; a seventh bird, equipped with a direction recorder, provided information on directional preferences exhibited on seven different trips. A foraging trip usually consisted of a number of flights interrupted by a small number of dives probably performed to explore the site for prey availability. True foraging occurred during the last stops in the outbound trip, after which the bird returned to the nest with a single flight or a sequence of a few flights. The duration of nocturnal trips was significantly longer than diurnal trips, possibly due to a preference for the familiar marine environment shown by birds when they are not 'on duty' in the nest. The majority of dives consisted of V-shaped dives in which birds descend to a maximum depth and then start ascending. A clear diurnal variation of the dive depth, which never exceeded 43 m, was recorded. Our results show that the new types of recording devices can be used to answer basic questions about the foraging strategies of marine birds.  相似文献   

13.
Trail laying behaviour during food recruitment in the antLasius niger (L.)   总被引:4,自引:0,他引:4  
Summary The trail-laying behaviour of foragers of the antLasius niger was observed in the laboratory on a 20 cm bridge between the nest and the food source. We measured both the frequency of trail laying, as defined by the proportion of trips during which trail laying occurred, and its intensity, as defined by the number of marks laid during one bridge crossing.Foragers do not exhibit trail-laying behaviour until a food source is discovered. Trail laying then occurs more or less equally both to and from the nest, and both its frequency and intensity decrease as the recruitment proceeds. Foragers from very small colonies less than a year old appear to have quantitatively the same trail laying behaviour as those from older and much larger colonies.Groups of recruiters and recruits were individually marked. Their trail laying intensity was similar, both for trips to and from the nest, and for an ant's first, second, third and fourth trip. The frequency diminished rapidly with the number of trips made by each individual, and was 2–3 times higher for recruiters than for recruits, for trips both to and from the nest. Even though foragers stop marking after a variable number of passages, they continue to move between the nest and the food source, and other ants start marking. Different foragers appear to have widely different levels of trail laying, although we cannot say whether these differences are stable between different recruitments.Trail laying is strongly affected by the foragers' position on the bridge, especially for ants returning to the nest which lay up to five times more on the segment closest to the source than that closest to the nest. Foragers on a weakly marked trail appear to mark more than those on a well-marked trail. However, this effect is weak and could partly be attributed to their lower speed.Finally, a model using the experimental data gathered on the individuals' trail-laying behaviour reproduced satisfactorily the colony's overall trail laying.  相似文献   

14.
As seabirds are central place foragers during breeding, their provisioning behaviour and their ability to face variable energy demand from the chicks is expected to vary with environmental conditions. The provisioning behaviour of female rockhopper penguins Eudyptes chrysocome filholi was recorded over the chick‐rearing period at Kerguelen (KER) and Crozet (CRO) archipelagoes (two very distinct marine environments), using time‐depth recorders, or VHF transmitters coupled with an automatic recording station. No influences of the method have been found on the average foraging trip durations. Some previously undescribed short and multiple trips within a day were recorded using the automatic recording system. These multiple trips (6.8 h) were mostly performed with <5 days old chicks, a period during which feeding rates were the highest (1.1 meals per day), at both sites. During the brooding period, both KER and CRO females mainly performed daily trips of increasing duration (2 h longer at CRO) and at decreasing frequency. During the crèche compared to the brooding period, females from KER performed slightly fewer daily trips (0.6 per day) and more (<3 days) overnight trips, while females from CRO performed very few daily trips (0.1 per day) and more overnight trips, some of them being long trips lasting 5 to 29 days, mostly initiated during the transition between the brooding and the crèche periods. The result fit the hypothesis that long trips permit females to restore and/or maintain their body condition at more distant foraging places. It seemed that chick developement during the brooding period and environmental factors during the crèche period conditioned trip duration of females. Due to more long trips at CRO, the female feeding frequency was twice as high at KER than at CRO during the crèche period, while males participated in the feeding duties. Based on differences in female behaviour, we hypothesize that the male's contribution is likely to differ strongly from one site to another, and may buffer the possible decrease in female feeding frequency by feeding the chicks if food is less abundant.  相似文献   

15.
Maternal attendance behaviour was studied in Antarctic (Arctocephalus gazella) and subantarctic fur seals (Arctocephalus tropicalis) which breed sympatrically at subantarctic Macquarie Island. Data on attendance were obtained using telemetric methods. Both species undertook two types of foraging trips: overnight foraging trips which were of less than 1 day duration and occurred exclusively overnight, and extended foraging trips which lasted longer than 1 day. The mean duration of overnight foraging trips was 0.43 and 0.39 days, while the duration of extended foraging trips was 3.6 and 3.8 days in A. gazella and A. tropicalis, respectively. The duration of overnight and extended foraging trips did not differ significantly between species. Two types of shore attendance bouts that differed in duration were also observed in these species. Short attendance bouts lasted less than 0.9 days, while long attendance bouts lasted longer than 0.9 days. Short attendance bouts lasted 0.4 and 0.5 days, while long attendance bouts lasted 1.6 and 1.7 days in A. gazella and A. tropicalis, respectively, and did not differ significantly between species. The most significant differences between the attendance behaviour of both species was in the percentage of foraging time allocated to overnight foraging trips (15% and 25% in A. gazella and A. tropicalis, respectively), and the percentage of time spent ashore (30% and 38% in A. gazella and A. tropicalis, respectively). The nearness of pelagic waters to Macquarie Island is considered to be the main reason that lactating females are able to undertake overnight foraging trips. These trips may be used by females as a means of optimising the costs of fasting and nursing ashore. Females may be able to save energy by only nursing pups when milk transfer efficiencies are high, and reduce the time and energy costs of fasting ashore when milk transfer efficiency is low. Of the female A. gazella that still carried transmitters at the end of lactation, 83% continued regular attendance for between 21 and 150 days post-lactation (when data collection ceased). Overwintering of A. gazella females at breeding sites has not been previously reported in other populations. Accepted: 10 November 1998  相似文献   

16.
Several field trips to India, Africa, Southeast Asia and South America were recently made to review and analyze disease problems related to capture and transportation of non-human primates. Wild primates are often exposed to a variety of diseases as they come into contact with people and other animals prior to shipment. These include tuberculosis, measles, shigellosis and various simian viruses. Even with the best trapping methods, extensive advance planning with cargo centers of various air terminals is necessary for proper handling of shipments. More and more frequently, airlines personnel fail to take even the most basic care of their live animal cargo. Specific recommendations are made to improve overseas trapping, handling and transportation procedures to reduce infectious diseases in imported primates.  相似文献   

17.
Females of Dawson's burrowing bees have a well-defined brood cell cycle involving cell construction, waxing, provisioning, egg laying, and cell capping. In one study population, nesting bees built smaller brood cells for offspring of lower weight and larger ones for heavier offspring, demonstrating their ability to anticipate the desired size of an offspring at the outset of a brood cell cycle. Furthermore, individual females varied the number of provisioning trips made per brood cell cycle by a factor of two or more, apparently exercising control over the amount of brood provisions supplied to an offspring. The size distribution of emerging males at two widely separated locations in 1997 was nearly identical to that recorded in 1995. These findings suggest that the production of small males (minors) is the result of active female control rather than the product of food shortages that force females to undersupply some brood cells. Female foraging decisions resulted in a bimodal distribution of weights of mature dormant larvae at one site in 1997. However, the times required to complete brood cell cycles at this site were not distributed bimodally. This result stemmed in part from daily variation among females in the duration of their provisioning trips as well as from seasonal variation in provisioning trip times. When provisioning trips lasted longer, females tended to make fewer trips per brood cell cycle, and so were presumably more likely to produce minor sons. As a result, the weight of an offspring was not tightly linked to the time investment required to produce it, making it difficult to compare the relative costs of minors and majors in terms of maternal time investments.  相似文献   

18.
Movements, diving and foraging behaviour of grey seals (Halichoerus grypus)   总被引:2,自引:0,他引:2  
This study presents the first direct observations of the movements and behaviour of free-ranging grey seals at sea. Radio and ultrasonic transmitters were attached to three sub-adult male grey seals which were then tracked from a suitable vessel. Behaviour at sea fell into one of three categories: travelling between haul-outs, short duration trips, and resting adjacent to haul-out sites. Travelling was characterized by direct, relatively fast horizontal movement and by V-shaped dive profiles. During short duration trips the seals swam slower and invariably exhibited square-wave dive profiles, spending approximately 60% of total dive duration at the maximum depth. Resting involved shallow dives close to haul-out sites and an absence of directed lateral movement.
The excellent navigational abilities of grey seals are illustrated by the rapid, direct swimming between distant haul-out sites. It is proposed that short duration trips are specifically for foraging because of their association with other piscivores, and because swimming was slow and mostly on or near the sea bed (grey seals are known to feed almost exclusively on demersal and benthic fish). These trips accounted for only 14% of the nine days that seal 1 was tracked. It is also proposed that the habit of diving to the sea bed whilst travelling between distant haul-out sites is to allow opportunistic foraging with only a small increase in total swimming distance.  相似文献   

19.
Radiotelemetry was used to assess the distribution and diving behaviour of Rock Shags Phalacrocorax magellanicus and Red-legged Cormorants Phalacrocorax gaimardi breeding in sympatry, and Rock Shags breeding in isolation. When breeding in sympatry there was little overlap in the foraging locations of the two species, with the highest densities of each species separated by 10 km. Red-legged Cormorants fed significantly closer to the breeding colony than did Rock Shags and undertook shorter foraging trips, making almost twice as many foraging trips per day as Rock Shags. Rock Shags breeding in isolation had a shorter foraging range than the birds breeding in sympatry with Red-legged Cormorants and foraging trip duration was significantly shorter. However, the number of feeding trips per day was similar between areas of sympatry and allopatry. Differences in the foraging ecology of Rock Shags in areas of sympatry and allopatry may be due to interspecific competition, which forces niche differentiation. The distance between foraging sites, the speed of movement of the prey, a species tendency to move into prey-depleted areas and the length of the breeding season (during which the birds are constrained to be in the same area) may play critical roles in determining the extent to which differential area use by competitors is a strategy that benefits both parties.  相似文献   

20.
J. P. Croxall    D. R. Briggs    A. Kato    Y. Naito    Y. Watanuki    T. D. Williams 《Journal of Zoology》1993,230(1):31-47
The pattern and characteristics of diving in two female macaroni penguins Eudyptes chrysolophus was studied, during the brooding period, using continuous-recording time-depth recorders, for a total of I8 days (15 consecutive days) during which the depth, duration and timing of 4876 dives were recorded. Diving in the first 11 days was exclusively diurnal, averaging 244 dives on trips lasting 12 hours. Near the end of the brooding period trips were longer and included diving at night. About half of all trips (except those involving continuous night-time diving) was spent in diving and dive rate averaged 14–25 dives per hour (42 per hour at night). The duration of day time dives varied between trips, and averaged 1.4–1.7 min, with a subsequent surface interval of 0.5–0.9 min. Dive duration was significantly directly related to depth, the latter accounting for 53% of the variation. The average depths of daytime dives were 20–35 m (maximum depth 11 5 m). Dives at night were shorter (average duration 0.9 min) and much shallower (maximum 11 m); depth accounted for only 6% of the variation in duration. Estimates of potential prey capture rates (3–5 krill per dive; one krill every 17–20 s) are made. Daily weight changes in chicks were directly related to number of dives, but not to foraging trip duration nor time spent diving. Of the other species at the same site which live by diving to catch krill, gentoo penguins forage exclusively diurnally, making longer. deeper dives; Antarctic fur seals, which dive to similar depths as macaroni penguins, do so mainly at night.  相似文献   

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