Micronekton of the North Pacific

1. INTRODUCTION 1.1 Working Group History 2. SPECIES COMPOSITION AND DISTRIBUTION PATTERNS RELATED TO WATER MASSES 2.1 Mesopelagic Fishes 2.1.1 Dominant families 2.1.2 Large-scale feeding and/or spawning migration or expatriation? 2.1.3 Definition of water masses 2.1.4 Species composition 2.2 Crustacean Micronekton 2.2.1 Euphausiids 2.2.2 Mysids and decapods 2.3 Cephalopod Micronekton 2.3.1 Family Enoploteuthidae 2.3.2 Family Gonatidae 2.3.3 Family Onychoteuthidae 2.3.4 Family Pyroteuthidae 2.3.5 Other cephalopods 3. VERTICAL DISTRIBUTION PATTERNS 3.1 Mesopelagic Fishes 3.1.1 Significance of diel vertical migration 3.1.2 DVM patterns 3.1.3 Ontogenetic change in DVM patterns 3.2 Crustacean Micronekton 3.3 Cephalopod Micronekton 4. BIOMASS PATTERNS 4.1 Micronektonic Fish 5. LIFE HISTORY 5.1 Fish Micronekton 5.1.1 Age and growth 5.1.2 Production 5.1.3 Reproduction 5.1.4 Mortality 5.2 Crustacean Micronekton 5.2.1 Age and growth 5.2.2 Production 5.2.3 Reproduction and early life history 5.2.4 Mortality 5.3 Cephalopod Micronekton 5.3.1 Age and growth 5.3.2 Production 5.3.3 Reproduction and early life history 5.3.4 Mortality 6. ECOLOGICAL RELATIONS 6.1 Feeding Habits 6.1.1 Fish micronekton 6.1.2 Crustacean micronekton 6.1.3 Cephalopod micronekton 6.2 Estimating the Impact of Micronekton Predation on Zooplankton 6.2.1 Predation by micronektonic fish 6.3 Predators 6.3.1 Cephalopods 6.3.2 Elasmobranchs 6.3.3 Osteichthyes 6.3.4 Seabirds 6.3.5 Pinnipeds 6.3.6 Cetaceans 6.3.7 Human consumption 6.4 Predation Rate 6.5 Ecosystem Perspectives 6.6 Interactions between Micronekton and Shallow Topographies 7. SAMPLING CONSIDERATIONS 7.1 Net Trawling 7.1.1 Sampling gears 7.1.2 Sampling of surface migratory myctophids 7.1.3 Commercial-sized trawl sampling 7.1.4 Sampling of euphausiids and pelagic decapods 7.2 Acoustic Sampling 7.2.1 Acoustic theory and usage 7.3 Video Observations (Submersible and ROV) 8. SUMMARY OF PRESENT STATE OF KNOWLEDGE 8.1 Fish Micronekton 8.2 Crustacean Micronekton 8.3 Cephalopod Micronekton 9. RECOMMENDATIONS 10. REFERENCES 11. APPENDICES (122 page document)

Interim report on the progress of an inventory of artesian wells in Florida: leading to the enforcement of sections 370.051 - 370.54, Florida statues

One of the causes of lower artesian pressure, water waste and aquifer contamination is the misuse and insufficient care of artesian wells. In 1953, Senate Bill No. 57, entitled "An Act to Protect and Control the Artesian Waters of the State" (see Appendix) became a law. This law was passed through the efforts exerted by leading members of the Senate and the House of Representatives, who understood the need for a wise and controlled expenditure of our most valuable natural resource. The State Geologist and his authorized representatives were designated by this law to enforce this conservation measure; however, no financial provision was included for the 1953-55 biennium. The proposed program of the Florida Geological Survey for this biennium did not include the funds nor provide any full-time personnel for the enforcement of this statute. As a result, little actual work was accomplished during these two years, although much time was given to planning and discussion of the problem. Realizing that this program could provide additional basic data needed in the analysis of the water-supply problem, the State Geologist sought and was granted by the 1955 Legislature adequate funds with which to activate the first phase of the enforcement of Florida Statute No. 370.051-054. Enumerated below is a summary of the progress made on this investigation as outlined previously: 1. Data have been collected on 967 wildly flowing wells in 22 counties. 2. Chloride determinations have been run on 850 of the 967 wells. 3. Of the 967 wells, 554 have chlorides in excess of the 250 ppm, the upper limit assigned by the State Board of Health for public consumption. 4. Water escapes at the rate of 37, 762 gallons per minute from these 967 wells. This amounts to 54, 377, 280 gallons per day. The investigation is incomplete at this time; therefore, no final conclusions can be reached. However, from data already collected, the following recommendations are proposed: 1. That the present inventory of wildly flowing wells be completed for the entire State. 2. That the current inventory of wildly flowing wells be expanded at the conclusion of the present inventory to include all flowing wells. 3. That a complete statewide inventory program be established and conducted in cooperation with the Ground Water Branchof the U.S. Geological Survey. 4. That the enforcement functions as set down in Sections 370.051/.054, Florida Statutes, be separated from the program to collect water-resource data and that these functions be given to the Water Resources Department, if such is created (to be recommended by the Water Resources Study Commission in a water policy law presented to the 1957 Legislature). 5. That the research phase (well inventory) of the program remain under the direction of the Florida Geological Survey. (PDF contains 204 pages.)

Influence of Water Depth on the Rate of Expansion of Giant Cutgrass Populations and Management Implications

Giant cutgrass ( Zizaniopsis miliacea (Michx.) Doell. & Asch.), a tall emergent grass native to the southeastern United States, was studied in Lake Seminole where it formed large expanding stands, and Lake Alice where it was confined to a stable narrow fringe.

On Selecting the excess temperature to minimize the entrainment mortality rate

In selecting an excess temperature at which to operate a power plant cooling system it has been customary to consider only thermal stresses and to use the ratio of the number of organisms killed to the number of organisms entrained. This frequently leads to the selection of a low excess temperature, AT, which, in turn, requires a large volume flow of cooling water. When mortalities due to physical and chemical stresses are included and the total number of entrained organisms killed is taken as the measure of the environmental damage, it becomes evident that the choice of a low excess temperature is seldom, if ever, best.

A method for estimating the rate of shedding of tags from yellowfin tuna

ENGLISH: The present paper describes a new method for estimating the shedding rate of tags. The method utilizes not only data on tagging and recovery of fish marked with two tags but also data from those marked with one. One important advantage of the new technique is that the estimates of the shedding rates are free from distortion caused by variations in fishing intensity during the total recovery period. The idea of this method appears to be implicit in a short note by Gulland (1963). This technique has been applied to the data obtained by the Inter-American Tropical Tuna Commission in a tagging cruise off the west coast of southern Baja California, during June 1963, at which time both single and double-tagged yellowfin tuna were released. Details of the tagging procedure and equipment have been described by Fink (1965b). The results presented in the present paper are for yellowfin tuna tagged with dart tags. Estimates of shedding should be made separately for each species investigated and also for each type of tag used, since these rates may be variable and often unexpectedly high (Springer and McErlean 1961, Chadwick 1963). SPANISH: El presente estudio describe un nuevo método para estimar las tasas del desprendimiento de marcas. El método emplea no solamente los datos sobre la marcación y recobro de peces marcados con dos marcas, pero también datos de los peces marcados con una marca. Una ventaja importante de la nueva técnica, es que las estimaciones de las tasas de desprendimiento son libres de alteración, causada por las variaciones en la intensidad de pesca durante el período total de recobro. La idea de este método parece ser implícita en un breve apunte por Gulland (1963). Esta técnica se ha aplicado a los datos obtenidos por la Comisión Interamericana del Atún Tropical, en un crucero de marcación efectuado frente a la costa occidental al sur de Baja California, en junio de 1963, tiempo en el cual fueron liberados atunes aleta amarilla marcados tanto con una como con dos marcas. Los detalles del procedimiento de la marcación y del equipo usado han sido descritos por Fink (1965b). Los resultados presentados en este estudio, pertenecen al atún aleta amarilla marcado con marcas de dardo. Las estimaciones del desprendimiento deben efectuarse separadamente para cada especie que ha sido investigada y también para cada tipo de marca usado, ya que estas tasas pueden ser vaiables, y a menudo inesperadamente altas (Springer y McErlean 1961, Chadwick 1963). (PDF contains 20 pages.)

Zum Stellenwert von Fischmehl in der Aquakultur

The worldwide aquaculture production amounts to about one third of the world fishery catch. While the world fishery catch in the last years is stagnating and an increase is not to be expected, the aquaculture rose by about 10 % annually. This rate of growth is also predicted for the next years. Fish meal and oil forms a key position for the further development of aquaculture, specially for carnivorous fish species, of which the salmonids will gain an increasing economic importance, not only on the European, but also on the Japanese and American markets. Without an adequate supply of fish meal and oil for the production of these fish species, the expected product quality cannot be realized under economic conditions. Fish meal and oil are commonly produced from small pelagic fish species, which, at present and in the near future, have no importance for direct human consumption. Since December2000 the use of fish meal and oil in Germany is only allowed for use in aquaculture and petfood. However, conclusive arguments for a ban on the utilization for other animal feeds do not exist so far. The European Union continues to allows feeding of other animals – except ruminants – with fish meal under certain control measures.

The growth and survival rate of Oreochromis niloticus fries fed (private) with varying percentages of Leucaena leucocephala leaf meal based diets

A-ten-week feeding trial was carried out to evaluate the growth and survival rate of Oreochromis niloticus fed with varying percentage levels of Leucaena leucocephala leaf meal based diets. The substitution rates of L.leucocephala leaf meal for groundnut cake in the various diets were 0% - Diet 1, 25% - Diet 2, 50% - Diet 3 and 75% - Diet 4. Ten fries with an average weight of 0.44g were stocked at the rate of 10 fish per bowl and fed at 5% body weight. Diet 1 with 0% inclusion of Leucaena leaf meal gave a significant difference (P>0.05) in growth and survival rate compared with diets 2, 3 and 4. The water quality parameters recorded were appropriate for fish culture

The growth and survival rate of (private) Oreochromis niloticus fingerlings fed with varying percentages of Leucaena leucocephala leaf meal based diets

A-ten-week feeding trial was carried out to evaluate the growth and survival rate of Oreochromis niloticus fed with varying percentage levels of Leucaena leucocephala leaf meal as a substitute for groundnut cake. The levels in the various diets were 0% - Diet 1, 25% - Diet 2, 50% - Diet 3 and 75% - Diet 4. Ten fingerlings with an average weight of 0.44g were stocked at the rate of 10 fish per bowl and fed at 5% body weight. Diet 1 with 0% inclusion of leucaena leaf meal gave a significant difference (P>0.05) in growth and survival rate compared with diets 2, 3 and 4. The water quality parameters recorded were appropriate for fish culture