家蚕种质资源品种的人工饲料摄食性研究     

顾寅钰  李化秀  施新琴  王安皆  张凤林  赵德安  王玺兰 《北方蚕业》2014,(3):18-20

采用山东省蚕业研究所现有低成本人工饲料饲养本所家蚕资源品种,研究其摄食性,结果杂交种优于日系与中系,在收蚁与1龄期间是日系明显优于中系,至3龄起蚕日系的存活率也是明显高于中系,而在2龄期间存活下来的中系家蚕对人工饲料的摄食性优于日系。  相似文献   

Daily rhythm and seasonal variation of feeding habit of Pacific saury (Cololabis saira) in relation to their migration and oceanographic conditions off Japan   总被引：1，自引：0，他引：1  

HIROYA SUGISAKI  YUTAKA KURITA 《Fisheries Oceanography》2004,13(S1):63-73

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Social learning in fishes: a review   总被引：14，自引：0，他引：14  

Culum Brown  & Kevin N Laland 《Fish and Fisheries》2003,4(3):280-288

Animals acquire skills and knowledge from other animals, and fish are no exception. There is now strong experimental evidence that many species of fish exhibit social learning and traditional behaviours. Here, we review the literature pertaining to social learning in fish, focusing on (i) antipredator behaviour, (ii) migration and orientation, (iii) foraging, (iv) mate choice and (v) eavesdropping.  相似文献   

盘锦苇田钻心虫发生规律及防治措施     

王洋 《农业机械化与电气化》2014,(11):10-11

芦苇钻心虫是盘锦苇田经常发生的害虫之一,不但破坏苇田植被,还直接影响芦苇质量,降低芦苇产量。介绍芦苇钻心虫的形态特征、生活习性、发生规律,以及危害特点,提出防治措施,为苇田钻心虫的有效防治提供参考。  相似文献   

Maximum foraging ranges in solitary bees: only few individuals have the capability to cover long foraging distances   总被引：2，自引：0，他引：2  

Antonia Zurbuchen  Jeannine Klaiber  Silke Hein 《Biological conservation》2010,143(3):669-361

To preserve populations of endangered bee species, sound knowledge of their maximum foraging distance between nest and host plants is crucial. Previous investigations predicted maximum foraging distances of 100-200 m for small bee species and up to 1100 m for very large species based on mainly indirect methods. The present study applied a new and direct approach to experimentally investigate maximum foraging distances in solitary bees. One endangered and two common species of different body sizes, all of which restrict pollen foraging to a single plant genus, were established in a landscape lacking their specific host plants. Females were forced to collect pollen on potted host plants that were successively placed in increasing distance from fixed nesting stands. The maximum foraging distance recorded for the small Hylaeus punctulatissimus was 1100 m, for the medium sized Chelostoma rapunculi 1275 m and for the large Hoplitis adunca 1400 m, indicating that maximum foraging distances at species level have been underestimated. However, the capability to use resources on such a large spatial scale applied only to a small percentage of individuals as 50% of the females of H. punctulatissimus and H. adunca did not forage at distances longer than 100-225 m and 300 m, respectively. This finding suggests that a close neighbourhood of nesting and foraging habitat within few hundred meters is crucial to maintain populations of these species, and that threshold distances at which half of the population discontinues foraging are a more meaningful parameter for conservation practice than the species specific maximum foraging distances.  相似文献   

Ontogenetic diet shift in the June sucker Chasmistes liorus (Cypriniformes,Catostomidae) in the early juvenile stage     

J. D. Kreitzer  M. C. Belk  D. B. Gonzalez  R. C. Tuckfield  D. K. Shiozawa  J. E. Rasmussen 《Ecology of Freshwater Fish》2010,19(3):433-438

Kreitzer JD, Belk MC, Gonzalez DB, Tuckfield RC, Shiozawa DK, Rasmussen JE. Ontogenetic diet shift in the June sucker Chasmistes liorus (Cypriniformes, Catostomidae) in the early juvenile stage.
Ecology of Freshwater Fish 2010: 19: 433–438. © 2010 John Wiley & Sons A/S Abstract – Ontogenetic diet shifts are common in fishes and often occur during early life stages. The larval and early juvenile period is critical in the life cycle of the endangered June sucker, Chasmistes liorus (Teleostei: Catostomidae). High larval and juvenile mortality leads to low recruitment to the breeding population and hence a declining natural population. To understand diet composition and dynamics in June sucker at early life stages, diet was quantified and compared to available food items in the natural environment during the early juvenile stage. Rotifers (Brachionus sp.) were the primary diet item at week 10, but by week 12 a small cyclopoid copepod (Microcyclops rubellus) became predominant. Availability of diet items varied little across the experimental period. The increase in size of young suckers may explain this rapid dietary shift, but there are some inconsistencies with the size selection argument. This diet shift represents an important nutritional change that should be considered in development of diets for young June sucker and in assessing suitability of nursery habitats.  相似文献   

几个板栗优系生长结实特性的调查分析     

陈在新  李晓明 《湖北农学院学报》1999,19(2):134-136

对高接后３ａ，综合性状优良，品种、产地与成熟期均不相同的６个板栗优系的生长结实特性进行了调查与分析，明确了板栗优系生长结实的基本特性，结果母枝粗度和结果枝粗度、数量、着生部位与雌花序数的关系，为板栗良种选育和丰产栽培提供了一定的理论依据。  相似文献   

Prey‐type‐dependent foraging of young‐of‐the‐year fish in turbid and humic environments     

Mikael Jönsson  Lynn Ranåker  P. Anders Nilsson  Christer Brönmark 《Ecology of Freshwater Fish》2012,21(3):461-468

Abstract – Fish, which are generally visual foragers, experiences reduced reaction distance in visually degraded environments, which has consequences for encounter rates with prey. Small prey is detected at shorter distances than larger prey, and piscivores are therefore predicted to be more strongly affected by visual degradation. In experiments, roach (Rutilus rutilus) were fed two plankton prey types and pike (Esox lucius) were fed Daphnia and larval roach, in clear water, algal turbid water and water coloured brown by dissolved organic matter (DOM). Planktivorous foraging in roach was not affected by visual degradation, while pike foraging on both Daphnia and larval roach was. Pike showed increased reaction distance to Daphnia in visually degraded water, while it was severely reduced with roach as prey even if the visual range was not reduced below pike reaction distances in clear water. Pike foraging on Daphnia was not affected, but when foraging on roach, the reduced search efficiency was counteracted by increased attack rates. However, there was no increase in movement and no difference between turbid and DOM treatments. Effects on piscivores will likely become more pronounced at later life stages as prey size and the reliance on long‐distance detection increases at the same time as changing climatic conditions may further deteriorate the visual conditions in future.  相似文献   

Home range: A fractal approach     

Craig Loehle 《Landscape Ecology》1990,5(1):39-52

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Gastric evacuation in koayu Plecoglossus altivelis altivelis examined in aquaria     

Machiko  NISHINO  Keiichi  KAWABATA 《Fisheries Science》2003,69(4):819-822

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