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1.
Yuuki Kawabata Junichi Okuyama Hiromichi Mitamura Kimio Asami Kenzo Yoseda Nobuaki Arai 《Fisheries Science》2007,73(5):1147-1154
ABSTRACT: Post-release movement and diel activity patterns of hatchery-reared and wild black-spot tuskfish were examined using ultrasonic telemetry. Five hatchery-reared and four wild fish were released in the sandy bottom of Urasoko Bay, Ishigaki Island, Okinawa, Japan, and monitored using automated monitoring receivers from November 2005 to February 2006. Both hatchery-reared and wild fish tended to stay near the release site for over two weeks, before leaving the release site. Both hatchery-reared and wild tuskfish showed diurnal rhythm intermittently; signals were recorded more frequently in the daytime and less frequently in the nighttime, suggesting that the fish of both origins were active during the day and inactive during the night. These findings indicate that the one-year-old hatchery-reared tuskfish have some consistent behavioral characteristics with those of the wild. 相似文献
2.
Takashi Yokota Hiromichi Mitamura Nobuaki Arai Reiji Masuda Yasushi Mitsunaga Masashi Itani Hiroyuki Takeuchi Tatsuo Tsuzaki 《Fisheries Science》2006,72(3):520-529
ABSTRACT: In order to establish techniques for the stock enhancement of red tilefish Branchiostegus japonicus , it is important to understand the behavioral characteristic of both hatchery-reared and wild fish. Four hatchery-reared and six wild fish were released and tracked using acoustic biotelemetry in Maizuru Bay, Kyoto, Japan, from August 2003 to February 2004. Data for the four wild fish released and tracked from January 2003 to May 2003 were also referred to for analysis. The released fish moved around in relatively large areas within about 10 days after the release, and then three hatchery-reared and two wild fish settled and stayed within limited areas. Fish of both origins showed strong site fidelity and diel activity patterns, i.e. they were detectable in the day but not at night, probably due to hiding behavior in their burrows at night. However, some discrepancies between fish of both origins were detected by comparing their track terms and activity patterns in detail. These discrepancies are probably attributable to the differences in environmental conditions that the fish had experienced before release. 相似文献
3.
Migration success of hatchery-reared and wild sea trout smolts through the lower stretches and the estuary of a Baltic Sea river were studied. During 3 years, wild and hatchery trout smolts were implanted with acoustic transmitters and released 14 km upstream from the river mouth. In order to monitor their out-migration pattern, acoustic receivers were deployed along the migratory route. Data on number of fish detected and date and time of detections were analysed and the migratory performance of wild and hatchery-reared fish was compared. A significantly higher proportion of wild fish (80%) successfully migrated to the coast compared to fish of hatchery origin (27.5%) and migration was faster in wild smolts. Hatchery fish were larger and had a higher condition factor and lipid concentrations, which are proposed as possible reasons for the poorer migratory performance of the hatchery-reared fish. 相似文献
4.
Hiromichi Mitamura Yasushi Mitsunaga Nobuaki Arai Yukiko Yamagishi Metha Khachaphichat Thavee Viputhanumas 《Fisheries Science》2008,74(4):787-795
Abstract: The horizontal and vertical movements of eight immature hatchery-reared Mekong giant catfish Pangasianodon gigas were monitored using acoustic telemetry in Mae Peum Reservoir, Thailand between 2003 and 2004. The fish were monitored for between eight days and more than 9 months. All of the fish moved over the entire reservoir within approximately 40 days after release. Subsequently, the home range became small approximately 40 days after release. The fish preferred deep areas in the reservoir. The fish displayed diel horizontal and vertical movement patterns. The fish showed larger-scale horizontal movement during the daytime than at night. The fish repeatedly showed active vertical movement during the day, whilst there was little variation in swimming depth at night. Our results imply that the vertical movements of the fish were related to the environmental condition of the reservoir. 相似文献
5.
Tomoya MURAKAMI Satoshi AIDA Kouji YOSHIOKA Tetsuya UMINO Heisuke NAKAGAWA 《Fisheries Science》2004,70(5):839-844
ABSTRACT: This study is the first to report on the high occurrence of agglutinated pelvic fin membrane deformities in hatchery-reared black rockfish Sebastes inermis . For 5 years, this symptom was marked in hatchery-reared fish, with 58.7% of fish deformed on average (varying between 46.7 and 72.0%). The deformity was a peculiarity in hatchery-reared fish, but is negated in wild fish, and was not related to whether the fish broodstock originated from the wild or from a hatchery. Mark–release experiments showed that deformed fish were almost the same as normal hatchery-reared fish in growth and survival rates, and, theoretically, the recapture numbers of hatchery-stocked fish, estimated by deformity, almost coincided with actual recapture numbers, confirmed by otolith tagging. The results of the present study indicate that deformity in hatchery-reared black rockfish is useful as a stock separation tool. 相似文献
6.
Hatchery-reared Atlantic salmon, Salmo salar L., parr and wild smolts which were microtagged and released into rivers in north-east England were recaptured by the fisheries at West Greenland, Faroes and on the Irish west coast, by the homewater net fisheries and by rod fisheries in rivers in north-east England. No significant differences were observed in the patterns of exploitation of hatchery-reared and wild fish in the distant water fisheries. The distribution of tag recoveries in coastal waters was strongly influenced by the pattern of fishing effort which was concentrated in the middle of the fishery area, but recaptures tended to be biased towards the river of release. There were significant differences in the distribution of recaptures of fish released in different rivers and between hatchery-reared and wild fish from the River Wear. There were also differences in the timing of recaptures of hatchery and wild fish from this river in the coastal net fishery. Very few fish were recaptured in rivers other than the one in which they were released, and there was no significant difference between straying rates for hatchery and wild fish. The relative numbers of recaptures in the coastal fishery and in the home river was the same for translocated hatchery fish and wild fish, thus refuting the suggestion that hatchery-reared fish have a reduced ability to home. The distribution of recaptures within fresh water provides clear evidence of tributary-specific homing of hatchery-reared fish. 相似文献
7.
When reared in captivity, first-generation hatchery-reared Arctic charr, Salvelinus alpinus (L.), from Møkkeland lake, northern Norway, differed from wild-caught conspecifics from the same source. Incidence of caudal fin damage (used as an indirect assessment of aggressive interactions) was high amongst the wild-caught charr, and there was considerable mortality amongst these fish. By contrast, hatchery-reared fish displayed little evidence of fin damage, and mortalities were low. When the charr were held in mixed groups of wild-caught and hatchery-reared fish, the hatchery-reared fish showed the most extensive caudal fin damage. Weight losses and decreases in condition were also greatest amongst the hatchery-reared charr that were exposed to competition with wild fish. The hatchery-reared charr held together with the wild fish also suffered high mortality. Thus, aggression may have been selectively directed towards hatchery-reared fish in mixed groups. Taken together, the results suggest that the energetic costs may be high for the recipients of aggression. 相似文献
8.
Morphological abnormalities in eye location and/or body coloration are commonly observed in hatchery-reared juveniles of many
pleuronectid species, and have become one of the most serious problems in juvenile production for stock enhancement. In this
study, these morphological abnormalities of six pleuronectid species—barfin flounder Verasper moseri, slime flounder Microstomus achne, stone flounder Platichthys bicoloratus, starry flounder Pl. stellatus, cresthead flounder Pseudopleuronectes schrenki, and marbled sole Ps. yokohamae—were successfully classified into four morphological types [normal, two types of pseudoalbinism (normal-eye position or top-eye
position), and ambicoloration], following the same classification scheme proposed for other two pleuronectids. Based on our
results, the characteristics of each morphological type are quite similar among species. It is confirmed that the normal type
has the same ocular side and blind side characteristics as those of wild fish, not only in eye position and body coloration,
but also in scales or dentition. The pseudoalbino types have the blind side characteristics of wild fish on both sides, with
top-eye type in all characteristics, and normal-eye type in all other characteristics other than eye position. The ambicoloration
type has all the ocular side characteristics of wild fish on both sides. Therefore, the pseudoalbinism and ambicoloration
of hatchery-reared juveniles of pleuronectid species can be considered malformations of asymmetrical formation. Since this
process normally occurs during metamorphosis, the term “metamorphosis-related malformation” is proposed for the abnormal formation
of juveniles in pleuronectid species. 相似文献
9.
Abstract. Shortly after their release in two Norwegian lakes (3 hours to 3 weeks), hatchery-reared brown trout, Salamo trutta L., yearlings were recaptured, and their feeding was compared with that of wild brown trout. Investigations were conducted during three different periods (June, August and September). In all three periods most of the hatchery-reared fish started feeding immediately after their release. The amounts of exuviae from Ephemeroptera larvae and Chironomidae pupae found in the stomachs of hatchery-reared trout decreased with time, indicating that their feeding habits were influenced by a learning process. However, within one week of their release, hatchery trout appeared to be feeding on wild prey as well as did wild fish. 相似文献
10.
Hatchery-reared animals for stock enhancement should be competent to survive and grow at rates equivalent to those of wild
conspecifics. However, morphological differences are often observed, and pre-conditioning steps may be required to improve
the fitness of hatchery-reared juveniles prior to release. In the present study, hatchery-reared Scylla serrata juveniles were reared either individually (HR-solitary) or groups in tanks (HR-communal), the latter group being exposed
to intraspecific competition and foraging for food. After 21 days, both groups were compared to similar size wild-caught juveniles
in terms of morphometric measurements of carapace spination, abnormalities and carapace colouration. There were some limited
significant differences between HR-communal crabs and HR-solitary crabs in terms of length of 8th and 9th lateral spines and
in body-weight-carapace width ratio, but both treatments differed from wild crabs, which were heavier and had longer carapace
spines for their size. In contrast, both HR treatments exhibited common abnormalities including deformities in the shape of
the abdomen, in particular occurrence of an asymmetrical telson or a deeply folded telson. In all cases, abnormalities persisted
through moulting. Initially, carapace colour differed in all measures of colour between HR and wild crabs. However, these
differences reduced after a period of 4–8 days of conditioning on coloured tank backgrounds or dark sand or mud backgrounds,
without moulting. Similarly, hatchery-reared crabs exhibited very limited burying behaviour on first exposure to sediment,
but this increased to levels observed in wild crabs within 2–4 days. Thus, short-term conditioning of hatchery-reared crabs
on dark sediments may be effective in increasing predator avoidance and survivorship in released animals, and present results
suggest that this can be achieved after relatively short periods of 1 week or less. 相似文献
11.
为优化曼氏无针乌贼人工繁育技术,提高人工增殖苗种的产量与质量,采用实验生态学方法,对比分析了野生和养殖曼氏无针乌贼（Sepiella japonica）的表观形态、生化组分及其受精卵的形态差异,探究了光照周期与受精卵胶质外膜对曼氏无针乌贼胚胎发育的影响。结果显示：野生和养殖曼氏无针乌贼的表观形态、生化组分均存在显著差异,野生群体性成熟规格远大于养殖群体,肌肉和肝脏组织中的脂肪含量显著低于养殖群体（P<0.05）,卵巢中的蛋白质含量则显著高于养殖群体（P<0.05）;养殖亲体所产黑卵在12D12L光照周期条件下孵化率最高,所产白卵在24D和24L条件下孵化率最高,野生亲体所产卵在24D和12D12L条件下孵化率最高;随光照时间的延长,受精卵的平均孵化时间具有先增加后减小的趋势,表明光照周期是影响曼氏无针乌贼胚胎发育的重要因素;实验发现,将受精卵胶质外膜剥离处理后,养殖亲体所产黑白卵的平均孵化时间具有减少的趋势,但孵化率显著下降（P<0.05）。综上所述,建议在曼氏无针乌贼人工苗种生产过程中,尽量选用大规格野生乌贼作为繁育亲体。此外,在受精卵孵化期间,应对孵化池进行适当遮光处理,避免受精卵长时间暴露于强光照环境中,以提高孵化率和仔乌成活率。本实验研究结果可为曼氏无针乌贼人工苗种繁育技术优化提供参考。 相似文献
12.
Yukinori Shimada Naoto Murakami Tatsuo Tsuzaki Tadahisa Seikai 《Fisheries Science》2007,73(2):364-370
ABSTRACT: To improve stock enhancement strategies, the influences of repeated cross-breeding on several traits were studied in hatchery-reared juveniles of the Japanese flounder. Ten families (seven caught in the wild and three from cross-bred brood fish) were produced by artificial fertilization. Ninety-four days after hatching, we investigated settlement, burying in the sand and escape behavioral traits, and then measured tolerance of high salinity and six morphological traits. Juveniles from the repeatedly cross-bred brood fish showed significantly higher growth and tolerance than those from the wild-caught brood fish. Among the behavioral traits, a significantly lower settling speed and incidence of burying in the sand were observed in the juveniles from the repeatedly cross-bred families. Heritability ( h 2 ) of growth traits was more than 0.2 in both origins, while that of other traits was close to zero. These results suggest that repeated cross-breeding of Japanese flounder under hatchery conditions improves growth performance and leads to the loss of certain behavioral traits that are considered essential to survival in wild environments. 相似文献
13.
Paulo Jorge Gavaia Susana Domingues Sofia Engrola Pilar Drake Carmen Sarasquete M Teresa Dinis & M Leonor Cancela 《Aquaculture Research》2009,40(14):1585-1593
The Senegalese sole is a marine pleuronectiform that naturally occurs in Southern Europe and Mediterranean region where it is being produced in aquaculture, in particular in Portugal and Spain. The aim of this study was to assess the quality of hatchery-reared larvae in comparison with those reared in the wild, and determine to which extension wild growing larvae are also affected by skeletal deformities. The main structures affected included those forming the axial skeleton, the caudal fin complex and both anal and dorsal fins, with the most prevalent anomalies affecting caudal vertebrae and arches. Hatchery-reared fish presented a higher incidence of deformities (79%) compared with the 19% observed in wild specimens. In wild postlarvae collected in Autumn no deformities were observed. This work clearly shows that wild Senegalese sole present less skeletal deformities than those hatchery-reared during larval stages, indicating a selective mortality of wild deformed fish and/or an effect of aquaculture-related rearing conditions in the development of skeletal deformities in sole. 相似文献
14.
. Atlantic salmon, Salmo salar L., parr and smolts from three Norwegian rivers were examined with respect to whether or not they had been released from a hatchery. The hatchery background was known for some released fish and could be ascertained for others from their aberrant body morphology and eroded fins. Fish released after one winter in a hatchery had opaque otoliths like the fish examined from two hatcheries. Naturally produced fish showed a distinct, seasonal growth pattern in the otoliths, alternating between opaque summer zones and hyaline winter zones. Fish released as fry showed an otolith pattern similar to that of naturally produced fish. A test revealed little discrepancy between two independent otolith readings even though the test reading was conducted without any information about the fish accompanying the otoliths. The results suggest that examination of otoliths may help distinguish between juveniles that are hatchery-reared and juveniles that are naturally produced in the river, provided that the hatchery-reared fish have a 1-year history in the hatchery prior to release. 相似文献
15.
G. J. A. Kennedy C. D. Strange R. J. D. Anderson P. M. Johnston 《Aquaculture Research》1984,15(1):15-25
Marked hatchery-reared smolts were released into the River Bush on the 1 May and 19 May 1980. and the time for their descent to trapping facilities was monitored. Of the smolts recaptured in each experiment 56.2% and 75.8% respectively descended the 3.5 km to the traps within 48 h, and the overall patterns of their downstream movements were found to be correlated to that of wild smolts. Smolts migrating from control tanks did so more slowly than those released into the river, and were not correlated with the movements of wild smolts. The feeding of recaptured hatchery smolts was compared with that of wild smolts for up to 11 days after the start of each experiment. It was found that most invertebrate groupings were not consumed at significantly different levels in the two groups, and that hatchery-reared fish began feeding on invertebrate food within 9 hours of release. 相似文献
16.
Abstract. Fungal infection of sexually mature brown trout and char was associated with a particular type of Saprolegnia exhibiting a low degree of homothallic sexuality. Hatchery-reared brown trout were more severely infected (in terms of the % area of the body covered with the fungus) than were wild fish. The fins of hatchery-reared fish were particularly prone to Saprolegnia infection regardless of sex. In wild brown trout, a sexual difference in the pattern of infection was demonstrated. The flanks of the male fish appeared to be more prone to infection when compared with the female and there was a greater susceptibility of the caudal and ventral fin of the female when compared with the male. Evidence is presented which suggests that the incidence of infection in mature male salmonid fish prior to spawning is significantly greater than in the females. This difference may not be apparent in spent fish after spawning. These findings are discussed in relation to the background concentration of fungal spores in the water, the behavioural characteristics of spawning fish and differences in epidermal structure. 相似文献
17.
Jennifer J. Cleary Ned W. Pankhurst Stephen C. Battaglene 《Journal of the World Aquaculture Society》2000,31(4):558-569
The effects of stress on reproductive steroids and the developing oocytes were investigated in female wild snapper Pagrus auratus caught by trap, 5-yr-old snapper caught as juveniles and reared in captivity, and 2- and 3-yr-old hatchery-reared snapper. Fish were confined post-capture for 1, 6, 24, 48 or 168 h. Stress resulted In an increase in plasma cortisol and concomitant decreases in 17β-estradiol and testosterone. In addition, there was an increase in the incidence of ovarian atresia. These results confirm that both wild and hatchery-reared snapper are highly susceptible to stress-induced impairment of reproduction. 相似文献
18.
J. Iglesias G. Ojea J. J. Otero & L. Fuentes T. Ellis 《Fisheries Management and Ecology》2003,10(1):51-59
Abstract Marked reared turbot, Scophthalmus maximus (L.) (594) were released onto an exposed beach nursery ground together with marked wild fish (438) of approximately the same size (4–6 cm TL) and were sampled at intervals for 38 days. A consistent ratio of marked wild: unmarked wild indicated that marking did not increase mortality. The wild 0-group turbot population size was estimated at 1540 at the time of release, indicating that hatchery-reared individuals could theoretically make a significant contribution to the local population size. However, the absolute and relative catches of the marked, reared fish were lower than those of the marked wild fish, and no reared fish were caught after 23 days. The higher mortality rate was attributed to both a smaller size and their hatchery-reared origin. The population dynamics of the 1994–1995 year-classes of wild turbot were also studied. Recruitment of post-larvae (3 cm) to the beach started in March and continued until October. Population size peaked over the August–October period. Juvenile turbot remained on the nursery beach until June of the following year when they presumably emigrated to deeper water. During this 15-month period their length increased from 3 to 12–15 cm. 相似文献
19.
Abstract Scales from hatchery-reared, stocked and wild mulloway Argyrosomus japonicus (Temminck and Schlegel) captured in the Georges River, and a library of mulloway scales from coastal New South Wales, were examined for the presence of scale checks. Checks specific for hatchery-reared fish were present in 100% of recaptured hatchery-reared mulloway; the origin of which was confirmed by the presence of a chemical mark in the otolith or fin spine. Up to 7% of wild mulloway were incorrectly classified as hatchery-reared on the basis of these checks. An abrupt reduction in salinity from 35 to 5 and 6 days starvation successfully induced checks in the scales of hatchery-reared mulloway. The marking efficiency for stocking checks was comparable to that obtained using oxytetracycline hydrochloride, and supports the short-term use of scale stocking checks to evaluate mulloway stock enhancement programmes in Australia. 相似文献
20.
Abstract. Dorsal fin condition was evaluated in two groups of hatchery-reared steelhead trout, Oncorhynchus mykiss (Walbaum), and compared to wild fish. Hatchery fish were reared either in nursery tanks with baffles or in isolation (1 fish/rearing space). Evaluations were conducted to determine differences in dorsal fin condition between these groups and to monitor the progression and severity of fin damage. Isolated hatchery and wild steelhead trout maintained perfect dorsal fins with characteristic white margins. Hatchery fish reared in nursery tanks with baffles experienced dorsal fin erosion that started when the fish were about 40mm total length (30 days after being on feed). This erosion continued until dorsal fin length averaged only 2·3 mm in fish 161–200 mm total length in contrast to an average dorsal fin length of 20·9mm in wild fish of the same size. 相似文献