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She was recognised for the key role she played in the EQC Action Group and her advice on commercial property insurance claims. She has devoted herself to human resource management for nearly two decades covering a wide spectrum of industries including hospitality, real-estate, broadcasting and media - where she spent most of her career. Dan Hughes Partner E: Trends in indicators of inequality and hardship to All Healthy Eating Physical Activity. Her role in the team includes refining and managing the Firm's Trusts Administration practice. Some of these have arisen from learning assessed against NCEA achievement standards.
In addition to the aforementioned factors that are associated with long-term maintenance, additional considerations apply when fishes are handled or subjected to various experimental manipulations.
Readers may obtain additional information concerning stress and stress responses in fishes from several reviews Bonga ; Barton Pain is fundamentally a psychological state of the conscious mind. This scientific organization explains that a definition of pain must avoid connecting it to an external eliciting stimulus Wall ; IASP Scientific difficulty arises when the definition is applied to animals for which the psychological experience of the conscious mind cannot be objectively discerned.
Scientists attempting to determine whether fish feel pain have thus developed surrogate metrics which, to date, have shortcomings. Overall, the weight of evidence in the fish species studied indicates that the experience of pain in mammals is not experienced in fish. To better understand the scientific merits of research articles on welfare-related aspects of aquatic animal physiology, some biases and limitations have recently been elucidated Rose ; Browman and Skiftesvik ; Rose et al.
Much of the confusion associated with pain research in animals, including fishes, is caused by a failure to distinguish nociception from the psychological event that must be present if pain is to occur Vierck ; Rose and Woodbury Nociception is the neural process of encoding noxious stimuli, with responses that may be autonomic or behavioral IASP While nociceptive responses often, but not always, precede pain in humans, they must be translated in specific regions of the conscious brain into a psychological experience in order to be classified and felt as pain.
Nociception is a common, but not a universal, characteristic of vertebrates, however. For example, elasmobranch species studied appear to lack nociceptive capabilities Coggeshall et al. Since publication of the Guidelines Use of Fishes in Research Committee , a number of studies, principally by Sneddon and coworkers, have suggested that the pain experience was demonstrated by Rainbow Trout Oncorhynchus mykiss e.
These experimentally induced behaviors have been challenged by Rose , , and Rose et al. Studies relying on endpoints of avoidance or escape from noxious stimuli as indicators of pain Dunlop et al. Several studies of nociception in bony fishes have suggested some differences between teleost fishes and mammals that have bearing on the perception of pain.
Anatomical and physiological studies have reported the occurrence of A-delta and C fiber nociceptor afferents in the trigeminal nerve of Rainbow Trout Sneddon et al. Although these studies revealed that A-delta type fibers were fairly numerous, only a small number of C fibers were found in the trigeminal nerve of Rainbow Trout Sneddon et al.
Anatomic observations relative to these two species led Braithwaite to claim support for the plausibility of pain in teleosts, yet the rare occurrence of C fibers contraindicates the feasibility of pain-induced suffering, or even intense, prolonged nociception in fish. With elasmobranchs, in particular sharks and rays, neither A-delta nor C fibers have been found Coggeshall et al. Elasmobranchs also appear to lack the spinal cord lamina I, a principal zone for synapsis of nociceptive afferent connections Cameron et al.
Other experimental and field descriptive studies have contraindicated the pain experience in some fishes. Resumption of feeding and apparent normal activity have occurred immediately, or within minutes of recovery from anesthesia following surgery Narnaware et al.
Biotelemetry studies have documented rapid recovery of normal behavior following transmitter implantation, as well as long-term survival and normal behavior Wagner and Stevens ; Newby et al.
Studies of catch-and-release angling have consistently demonstrated the resumption of normal activity immediately after release, or at most within relatively short times of release. Many instances of fish being recaught within minutes of release have been reported Schill et al. There is little debate that exposure to noxious stimuli, regardless of it being experienced as pain or not, is stressful from a behavioral standpoint; therefore, exposures to noxious stimuli should be minimized.
While firm in believing that research on live fishes is acceptable and essential, the UFR Committee recognizes the sometimes difficult task facing IACUCs that must develop institutional guidelines that are both functional for, and accepted by, their constituents.
All subjects of experimental procedures must be protected from potential physiological or behavioral disturbances and harm in order for the results to be accepted as representative of the population from which the experimental subjects were drawn. The factors that are detrimental to fish welfare have been well delineated by valid, objective indicators of physiological and behavioral well-being.
Scientific literature should inform an IACUC in developing specific policies, recommendations, or regulations concerning aquatic animal welfare. The use of sedatives or anesthetics to restrain fishes is often essential to prevent harm to the animals, particularly where invasive procedures are involved see section 7.
Sedation or anesthesia may also be important from the perspective of investigator safety, especially when handling large or otherwise hazardous subjects. Procedures described in the Guidelines provide additional information see section 7. Sedatives and Related Chemicals.
Whether fishes are being collected live for investigations, preserved for study in a museum, or processed to obtain data needed for fisheries management, investigators should observe and pass on to students and employees a strict ethic of habitat conservation, and respectful and humane treatment of the animals in sampling, handling, and euthanasia ASIH et al.
The UFR Committee recognizes that currently no field collection techniques exist that will cause zero mortality events in the population being sampled. Research goals will generally dictate appropriate sampling methods. Given a set of alternative sampling methods and collecting gears, investigators can select the ones which cause the minimum levels of habitat disturbance and mortality in target and non-target fish populations.
Gathering large series of animals from breeding aggregations should be avoided unless required to meet study objectives. Use of collecting techniques that damage habitat unnecessarily should also be avoided or performed to the minimum extent necessary to achieve study or sampling objectives. For example, trawling or other forms of dragged or towed gears is essential for documenting fish diversity or monitoring the health of fish populations; however, such gears can cause extensive disturbance to substrates, macrophytes, or other important structural elements of fish habitat.
Sampling equipment and strategies can be designed to minimize incidental capture of non-target species. Collecting gears, such as gill nets deployed for nonlethal sampling, should be checked frequently to avoid unnecessary mortality. Regardless of the purpose of the experiment—whether to manipulate abundance or to study behavior, reproductive potential, or survivability—mortalities within the population and disturbance to habitat should be kept to the minimum amount that the investigator along with the IACUC determines to be acceptable.
The reader should note that some content in section 5 is not restricted to field activities but can extend to laboratory situations as well. Research with fishes frequently requires capturing wild specimens from the field, whether for field-based studies—such as data recording, marking, and relocation—or for laboratory studies of live or preserved specimens.
Permits are issued by natural resource agencies of state, provincial, federal, and tribal entities in the United States and Canada see section 3. Permit applications generally request information about the research to be conducted, sampling methods, the areas to be sampled, and number and disposition of fish specimens to be collected. For a listing of state permitting agencies in the United States, as well as other useful information about collection of fishes, see Walsh and Meador Collection of fishes on federal lands often requires a separate special use permit obtainable from the agency responsible for managing the land.
The local, state, federal, and tribal authorities that issue collecting permits generally require collectors to notify them of the specific locations, dates, and proposed methods of sampling. Collection of fishes by federal personnel on private lands requires a permit approving access from the landowner. Generally, the questions being explored and the study design itself dictate the number of specimens required for an investigation.
Acquiring fishes for study generally involves the taking of a very small portion of the population or community present at a location. The general principle applied when sampling fishes is to take the fewest animals necessary to reliably address the hypothesis see section 2. The minimum number of fishes necessary to provide robust statistical results should inform the sampling protocol.
Depending on the gear and methods, and the amount of handling required, high mortality rates may result. This is especially true in investigations involving fish eggs and early life stages. However, high levels of juvenile mortalities and rapid recoveries from population reductions are both characteristic events in the life histories of many fish species.
Sampling by using visual surveys alone is not always sufficient. This is the case in habitats that are structurally and biologically complex, where fish biodiversity data is necessary for their conservation and management.
Small, cryptic fishes in coral-reef habitats, for example, are best collected by using small-scale sampling with ichthyocides; increased collection percentages of visually detected fish occurred with ichthyocide application Smith-Vaniz et al. The most commonly used ichthyocide is rotenone see section 8. The use of this chemical option has been diverse McClay ; its use had been indicated with the threat of exotics Rayner and Creese Robertson and Smith-Vaniz reviewed rotenone used by indigenous subsistence fishers and by fishery managers, as well as its toxicity and effects on other organisms.
Rotenone anesthetizes and dispatches fishes by blocking the cellular uptake of oxygen Singer and Ramsay A manual and SOP http: Investigation into alternative methods Marking is prudent, as is the availability of taxonomic expertise Walsh and Meador so to confirm the species present see section 8. Sampling fish in contaminants studies is often inherent in biomonitoring of aquatic ecosystems because of capabilities of fish to accumulate environmental contaminants and to respond physiologically.
Field procedures for sampling fish for chemical contaminants Hughes et al. Investigators need to be aware of whether an aquatic habitat to be sampled supports imperiled species, as well as how to identify those species in the field Warren and Burr Investigators can also determine if the habitats that support imperiled and nonimperiled species are considered areas of conservation concern and if species could be a focus of conservation concern Jenkins et al.
State wildlife action plans Association of Fish and Wildlife Agencies , http: Natural Heritage Programs http: Lists of state-protected species may be obtained from offices that issue collection permits and from the Web sites of NatureServe originally known as the Association of Biodiversity Information, http: A bulletin highlighting protected marine or anadromous fishes http: Lists of protected fishes in Canada, Mexico, and other foreign countries can be viewed online on the respective national Web sites such as the Species at Risk Act Public Registry, http: The collection of imperiled species is allowed only under special circumstances e.
Only noninvasive handling techniques handling that results in no harm whatsoever to the animal are to be used. Examples can include blood and milt collection, and certain fin clipping and tagging methods. If the goal of the research is to collect an imperiled species for live study, or if incidental capture is anticipated as bycatch, then any collection methods that may be injurious e. Conservation efforts for imperiled fish species frequently involve translocations, either among natural localities or from nature to propagation facilities and then back to nature.
The environmental laws governing translocations of imperiled fishes are complex and based on such matters as resource use, suitability and security of transplant sites, and the appropriateness of transplanted individuals among sites i.
All translocation efforts must be conducted by the agency with authority and responsibility for the species and area in question and should not be attempted by unauthorized individuals. The collection of fishes from natural populations for museum preservation is critical for 1 understanding basic biology and life history, 2 documenting and recording biodiversity, and 3 establishing reference collections essential for understanding evolutionary relationships and environmental effects ASIH et al.
Studies of ecosystem variation or delineation of new species frequently require collection of relatively large series sufficient for computing statistics on counts and measurements from multiple populations across geographic ranges Hughes and McCormick Sampling natural fish populations for these purposes typically involves broad surveys and collection of specimens in proportion to their occurrence in natural populations; moreover, such sampling may not be hypothesis-driven.
Studies of molecular systematics typically involve very small numbers of specimens, or small amounts of tissue removed from study fishes. Museum collections of fishes are also available for use in other types of research. Two important principles that should be followed in collecting fishes for museum preservation are 1 the numbers of specimens collected should be the minimum necessary to accomplish study goals, and 2 animals collected should serve a variety of studies.
Precise notations containing specific field data such as date, exact location, habitat type, etc. Specimens collected for museum deposition should be preserved in a manner that maximizes their utility for study and minimizes the need for additional collecting. Formalin fixation is the standard practice used to ensure long-term preservation quality of fish specimens.
Chemicals are often added to formalin to buffer the solution or to preserve color e. Fixation by these methods typically involves small pieces of tissue dissected from specimens that may be sacrificed by means other than immersion in formalin. Carcasses for long-term archiving as voucher specimens should be fixed in formalin and later transferred to alcohol.
Euthanizing fish prior to immersion in formalin should be practiced, provided that the sedative does not cause effects detrimental to the objectives of the research. A variety of chemicals, such as tricaine methanesulfonate MS , may be used to anesthetize or euthanize fishes see section 7. When study interests demand that specimens be fixed without prior treatment with sedatives, the specimens can be numbed in ice water, or for small fishes, immersed directly in liquid nitrogen see section 8.
Portions of animal specimens, including sperm, ova, embryos, tissues, and serum, are sometimes tissue banked. For example, the National Animal Germplasm Program http: Various iterations of specimen banking for retrospective analyses occur globally for a multitude of investigations, including environmental monitoring, genetics research, and systematics.
Fish tissue liver and muscle has been collected for the long-term storage of a variety of environmental specimens by the National Institute of Standards and Technology NIST, http: The choice of a sampling method should be dictated by worker safety, research objectives, seasonal considerations, and the habitat type to be sampled. Capture techniques should prevent or minimize injury and stress see section 4.
Live wells or tanks should be provided if fishes are to be kept for more than the time needed to collect essential metrics. Care should be taken to avoid accidental capture of nontarget species and to ensure release of incidentally collected individuals with minimal or no injury ASIH et al.
Species that may be dangerous to workers due to size or species-characteristic behavior or capabilities require additional precautions see sections 5. Several studies have shown electrofishing to be among the most effective techniques for obtaining fish assemblage data in freshwater habitats Yoder and Smith Electrofishing can be performed by wading methods or boat-mounted methods.
Appropriate electrofishing protocols should consider the sampling purpose and physical constraints of the environment e. Alternative sampling methods, such as seining, gill or trammel nets, trawls, cast nets, lift or push nets, rigid traps e. The sampling methods chosen should allow for efficient capture of the species and sizes of fish needed to address research objectives while minimizing injury and mortality of collected fishes and non-target organisms.
Multiple sampling gears may be required for the collection of a broad range of fish sizes or species or if diverse habitats are covered. Passive capture methods, such as set nets and traps, should be checked frequently enough to prevent unnecessary mortality of both target and non-target species. Prolonged restraint that causes physiological stress should be avoided. In some cases, use of a sedative or anesthetic agent to minimize stress may be advisable. Depending on the chemical agent and its mode of action in fish, one or more of these terms may apply.
However, use of MS in the field is limited because of an FDA requirement that food fish, including feral fishes that may be caught and eaten by humans, must go through a day withdrawal period prior to release or slaughter for human consumption Anderson et al. When handling the dry form of the chemical, personal protective equipment such as a respiratory mask and gloves should be used. See Coyle et al. Unlike many therapeutic drugs, these sedatives cannot be prescribed for extra-label uses i.
More specifically, if an appropriate grade of CO 2 is used, good management practices are followed, and local environmental requirements are met, the FDA has determined that regulatory action against the use of CO 2 as a fish sedative is unlikely. Currently, the eugenol-based product can be used as an immediate-release sedative for field applications where it is likely that fish will be sedated just once in their lifetime.
All other applications require a 3-day withdrawal period. With the use of any sedative, a small number of fish should be tested to determine a suitable dose within the allowable ranges and to ensure that the species will return to normal physiological and behavioral status within an acceptable recovery time. The animals must be kept under observation until appropriate recovery occurs see section 4. Used sedatives must undergo disposal in accordance with local, state, tribal, provincial, and federal regulations see also 5.
Species considered dangerous to humans are most often encountered under field conditions, yet the guidelines are similar for laboratory situations. Dangerous species should be handled in a manner that is safe for both the investigator and the animal being handled.
Investigators should be cognizant of safety regulations for their institution regarding the use of dangerous or venomous animals. Those regulations may include SOPs that limit access for only authorized personnel, specify use of protective clothing or handling devices, and dictate treatment of individuals injured by the animals, including first aid and procedures for obtaining follow-up medical care.
Special handling methods will depend upon the species being handled, the nature of the danger to the investigator, and the nature of the research effort. Overall, consulting the relevant literature and colleagues experienced with the species is of primary importance.
For general as well as specific information, with special reference to the marine environment, several books are available that are primarily written as cautionary first aid guides for scuba divers, free divers, and snorkelers who frequently come into contact with marine animals Halstead ; Cunningham and Goetz ; Auerback , as is information on the Divers Alert Network DAN Web site www.
Fishes will exhibit some degree of stress response when handled and transported. Methods of handling fishes vary with the species, the environment in which they are found, and the tradition and resources of a particular region or country Avault Stress responses can be reduced, however, by eliminating rough handling, rapid temperature changes, sudden water quality changes, abrasion, and excessively tight confinement.
Inappropriate handling and transport procedures can contribute to changes in blood profiles Ellsaesser and Clem and substantial mortalities Weirich ; Carmichael et al. Handling and transport procedures must be designed to minimize the effects of stress and thereby reduce immediate and delayed losses see section 4.
Some physiological changes that occur in response to handling and transport stressors are measurable and can be monitored. These changes include increased cardiac output, increased gill vascularity, and release of catecholamines and corticosteroid hormones Carmichael et al.
Handling of fishes in the field or in the laboratory is frequently characterized by increased susceptibility to disease thought to be mediated by immunologic suppression Wedemeyer Lymphopenia, neutrophilia, and lymphocyte nonresponsiveness have been noted as results of handling and transport stress Ellsaesser and Clem Clinical hematological values are available for some species Stoskopf b. Depending on the severity of the stressors and exposure time, mortality can result from osmoregulatory dysfunction and immunosuppression.
To mitigate stress associated with handling and transport, the investigator can reduce the number and severity of the stressors, minimize the duration of stressors, and minimize increases in metabolic rate. Harvesting techniques and preshipment treatment are important to the successful shipping of live fish Dupree and Huner Preconditioning treatments can involve the addition of sedatives to reduce metabolic rate, or salt or calcium to the transport water to prevent or reduce osmoregulatory dysfunction and resulting ionic imbalances Carmichael et al.
Feed should be withheld for 1 or 2 days prior to transport Weirich Generally, transports are less damaging to animals if done in cool weather. Proper equipment for transport should be used. Transport tanks should be well constructed and should be disinfected before use Avault The weight of fish that can be transported safely in a live-hauling vehicle depends on efficiency of the aeration system, duration of the haul, water temperature, fish size, and fish species Avault Maintaining acceptable ranges of dissolved oxygen, carbon dioxide, temperature, ammonia, and pH during transport is essential.
Fishes can be transferred between capture and transport units, or between transport units and holding units, by wet or dry transfer methods. Wet transfer involves transport of fishes in a container of water and minimizes direct contact with nets. Wet transfer usually results in less stress than dry transfer, where the net is used alone.
Ideally, fishes should be allowed to recover in the same or similar medium used for transport Carmichael et al. The length of time for recovery may vary depending upon conditions, the amount of handling, and research objectives, but 72 hours typically is considered a minimum following extensive handling see section 5.
Because the biological needs of each aquatic species and the nature of individual projects vary, only the most general recommendations are provided on temporary holding and maintenance.
Testing and comparing several methods of housing may be necessary in order to find the most appropriate for the needs of the species and the purpose s of the study. Ease of maintenance by animal keepers, though important, should not be the prime determinants of housing conditions; however, such ease generally ensures greater compliance with established maintenance protocols ASIH et al.
Normal field maintenance facilities should incorporate those aspects of the natural habitat deemed important to the survival and well-being of the animal. Adequacy of the maintenance facility can be monitored by observing changes in animal growth and weight, survival rates, activity levels, general behavior, and appearance Snieszko Nutritionally balanced diets should be provided, or natural foods should be duplicated as closely as possible.
Natural light and temperature conditions should be followed unless alteration of these factors is under investigation for achieving a desired effect e. Fish species have optimal thermal regimes Sylvester , and the immune system functions best within such ranges Bly and Clem Diseases occur during temperature windows as well, such as Edwardsiella ictaluri in Channel Catfish Hawke Frequency of tank cleaning should represent a compromise between the level of cleanliness necessary to prevent disease and the amount of stress imposed by frequent handling ASIH et al.
For culture, bait, or sportfish species, fishes are generally held in vats or tanks before shipment. This holding enables the producer to grade fish according to size and to administer drug therapies if necessary.
Holding also acclimates the fish for handling and transport Huner et al. When Channel Catfish are harvested from a pond, live cars or fish holding bags are used in the industry Huner et al. These methods generally are applicable to all pond-reared species. In pond holding situations, fishes might be moved to deeper water in which cases the use of recirculating pumps or aerators can be beneficial.
As with other containment systems, the holding tank needs to allow for the stocking density or the relation of fish biomass to available water volume. Water inflow and turnover rate must be considered because sufficient water exchanges are needed for good water quality. Oxygen available in the incoming water needs to exceed the metabolic oxygen consumption by fishes in the tank Casebolt et al. Sufficient aeration can be supplied by compressed air, injected or bottled oxygen, or agitation.
Sedatives can also be used to reduce the physical activities of fishes, if consistent with research objectives. Excess noise and vibrations should be avoided because such factors can produce acute or chronic stress response in fish Stoskopf see section 7. If extreme weather and environmental events occur, emergency preparedness measures may be necessary for future short-term maintenance of research animals.
For instance, excess feed storage, alternative water supplies, and back-up generators may need to be in place. Because numerous physiological processes can be altered upon handling and transferring fishes, acclimating or conditioning fish to their new environment lessens potential negative effects. If the physical and chemical qualities of the water supply for the temporary holding facility see section 5.
For example, fish in floating plastic bags with an atmosphere of oxygen above the water may be used to allow the captured fish to acclimate to the new water temperature. If differences are more substantial, gradually replacing the water in transport units with source water from the holding unit is a common practice that provides adequate time for fish acclimation. Useful notes on how to transport and acclimate live warmwater fishes are summarized in the Southern Regional Aquaculture Center Transportation of Warmwater Fish factsheets Loading Rates and Tips by Species Jensen a, https: Results obtained from careful collection and examination of blood and other tissues are often critically important to research on fishes Blaxhall ; Fange Sterile conditions for these procedures are often impossible to provide under field conditions, and care must be exercised to prevent injuries and stresses to the animals.
Samples of blood and body fluids can be obtained from fishes without compromising their survival, even from small specimens under grams Stoskopf a. Plastic syringes containing a small amount of anticoagulant such as sodium- or ammonium heparin or sodium citrate are suggested to prevent blood clotting. Study objectives will determine the proper selection of type, volume, and concentration of anticoagulant, if needed.
Three main techniques have been devised for collecting blood from fishes: The tail is the preferred site for blood sampling. The vessels running beneath the vertebrae of the fish can be sampled by using a lateral or ventral approach. Cardiac punctures from the ventral side are sometimes used in fusiform fishes or through the operculum in laterally compressed species. For repeated sampling, cannulae may be implanted in the dorsal aorta through the buccal cavity.
Blood from the caudal vessels may be collected directly into collection tubes by cutting off the tails of sedated fish that will be euthanized following the procedure. However, extraneous fluids and proteins that may influence cell quality often co-occur with this procedure.
Caution must be exercised to ensure that the method of sedation will not interfere with subsequent analyses. Additional information on sampling methods for the collection of blood from fishes has been described by Klontz and Smith , Smith et al.
Additional tissues that are useful for collection include otoliths, gills, kidney, thyroid, spleen, testes, ovaries, liver, heart, brain, and muscle. Collection of internal tissues typically requires sacrifice of the subject animals and must be preceded by appropriate anesthesia or euthanasia see section 8. These tissues can also be used for such purposes as contaminants analyses see section 5. Tissues may be used fresh or frozen, or placed in a fixation or preserving medium such as buffered formalin, ethanol, or methanol and then histologically processed Luna ; Presnell et al.
The purposes of some studies may be served by collections of scales, spines, or small pieces of fin, which can be accomplished with minimal effects on live fish and may be considered non-invasive sampling.
This is important when working with imperiled species and small populations see section 5. When transporting live tissues, the medium must have appropriate ionic and osmotic concentrations and may contain a sugar as an energy source.
Noncytotoxic antibiotics or antimycotic agents may be included to prevent the growth of bacterial and fungal organisms Jenkins a; Jenkins et al. Certain cell and nucleic acid stabilizers can make sampling of fish possible from remote locations for later tissue analysis in the laboratory Olivier and Jenkins, in press.
Tagged and marked animals have been studied to obtain information on their behavior, population dynamics, and ecology, all of which are essential for developing conservation and management strategies. Investigators can use both intrinsic and extrinsic identification systems, allowing the nature of the study to dictate the type of tag or mark employed. Integrated use of more than one tagging or marking technique helps ensure fish identification and is helpful in estimating tag loss rates.
Basic considerations for selecting a particular type of tag or mark in the context of the study objectives include potential effects on animal survival, behavior, and growth; tag permanency and recognition; number and size of the animals; stress of capture, handling, and marking; total costs; recovery of the marked fishes; and any required coordination among agencies, states, provinces, or countries Pine et al. Investigators should also determine if the animal will be at greater than normal risk to predation, if its desirability as a mate will be reduced, and if a risk of infection is increased substantially, as well as other potential impacts ASIH et al.
Because techniques for tagging and marking fishes have been extensively reviewed and are constantly evolving, literature reviews should inform the researcher McFarlane et al. The effects of marking on fishes depend on the physical condition of the fish at the time of release. Occurrence of injury is species and size specific, and smaller fishes may be more susceptible. Minor wounds caused by most tagging and marking procedures typically heal satisfactorily without treatment with antibiotics.
All sedatives or antibiotics administered must be used in a manner consistent with regulatory requirements. The use of external tags and marks has evolved over a long period of time McFarlane et al.
Both natural marks and artificial tags or marks are in common use in fisheries research, and each type offers different capabilities, as well as limitations. Natural, external marks include meristic characteristics, pigmentation, morphometric measures, and scale characteristics, but natural marks are subject to environmental and genetic influences. Fish scale shape and size, as well as circulus spacing, are frequently used.
The effective use of natural marks requires being well informed on fish life history. Multiple methods are available for generating artificial external marks on fishes. Alteration of fins or other body parts, in practice for over years, can be accomplished by clipping or hole punching. The selection of fins for clipping or removal is dependent upon the species under study; for example, clipping the anal fin of poeciliid males would be inappropriate because it functions as a copulatory organ, yet removal of the adipose fin of a salmonid would have negligible impacts ASIH et al.
Hot or cold branding, the process of marking by placing an apparatus e. Fishes should be anesthetized prior to branding. External colorants for marking fishes include dyes, stains, inks, paints, liquid latex, visible implant elastomers, and plastics that are administered by immersion, spraying, injection, or tattooing.
Care is needed for distinguishing external colorant marks of similar tones Curtis External tags are conspicuous by their color, shape, size, or location of attachment and are composed of various materials. Designed for hydroturbine passage survival studies, an external transmitter that is molded to the fish has shown utility Deng et al.
External tags commonly applied to fishes include dart nd t-bar anchor tags, disc tags, Carlin tags, and spaghetti or loop tags Guy et al. Dart and anchor tags are the most frequently used external tags Nielsen , but a high loss rate has been reported in some species Guy et al.
Proper insertion technique and use of small tags relative to fish size can reduce the potential for fish injury and tag loss Guy et al. Implanted coded wire tags, radio and acoustic telemetry transmitters, archival biologgers, passive integrated transponder PIT tags, visible implanted alpha numeric tags, otolith marks, and natural parasites are internal marking systems used to identify fish Prentice et al.
The use of a coded wire tag identification system has been tested for management and research applications with multiple genera of fishes Buckley and Blankenship including juvenile salmonids Liedtke et al. The coded wire tag is normally injected into cartilage, connective tissue, or muscle and is detected electronically later with a handheld device.
Each PIT tag carries a unique code that is relayed to a handheld or stationary reading device when the tag is within range. Advantages of PIT tags include a long lifespan and generally a high retention rate Freeland ; Guy et al. The PIT tag data can be read through soft and hard fish tissue; in seawater and freshwater; through glass, plastic, and metal containers; and when fishes are moving at some velocity.
Above certain fish size thresholds Tatara , they have little or no effect on fish growth, survival, or behavior Prentice et al. Various tags and methods are available for the PIT tagging procedures; information can be found at state websites e. Visible implanted tags are alphanumerically coded and made of polyester film. They are inserted subcutaneously into transparent tissue so that they remain externally visible Haw et al. Common tagging locations include transparent tissues posterior to the eye, in the lower jaw, or in fin membranes.
Tag retention varies by species, tag location within the body, and fish size; very small fishes may have insufficient transparent tissue to accommodate the size of the tag Griffiths Manipulating environmental temperature, feeding rates, photoperiod, external chemical baths, or labeled feeds can induce specific marks in fish otoliths.
Fishes being propagated under controlled conditions are ideal for such manipulations. Otolith microstructural features and induced marks are permanent and can be viewed and analyzed in fish of any age. Tetracycline and other fluorescent compounds e. Fish size, compound dosage and uptake method, and water chemistry can influence marking success with fluorescent compounds Beckman et al. Marking success is highest during times when fish growth is rapid Conover and Sheehan Otoliths and other calcified structures can also be marked with alkaline earth and rare earth elements Behrens Yamada and Mulligan or isotopically labeled compounds Munro et al.
Fisheries that require stock definitions and assessment of stocking success or dispersal of early life stages are well suited to otolith-marking techniques. Several taxonomic groups of fish parasites have been used as biological tags, and this method is best suited to the separation of relatively self-contained stocks of fishes MacKenzie Recovery of internal parasites used as biological tags is enhanced if parasites are associated with a specific anatomical site on the fish.
The decision to use a parasite as a natural mark on fish is determined by calculating the ratio of incidence of that parasite in one fish population to its incidence in another Wydoski and Emery Underwater biotelemetry involves attaching a device that relays biological information via ultrasonic or radio signals from a fish to a remote receiving system Cooke et al. Radio transmission is practical only in freshwater at relatively shallow depths ASIH et al. The selection of a tag or transmitter and the method and site of attachment or implantation is to be appropriate for the species and size of fish and performed by trained personnel.
Surgical implantation of transmitters into the coelom is common with free-ranging fishes. Use of the smallest and lightest transmitter that provides the desired signal type, strength, and battery lifespan will minimize tag loss and potential effects of transmitter attachment on fish survival, growth, and behavior.
External, neutrally buoyant transmitters have been developed for turbine-passage studies with juvenile salmonids at hydroelectric facilities Deng et al. With fish exposed to rapid pressure changes, external transmitters may decrease the likelihood of injury or death compared to surgically implanted transmitters Brown et al. Techniques to minimize skin irritation should be used following attachment of external transmitters Crook see section 7.
The development of techniques employing markers based on chromosome and nuclear DNA polymorphisms has been rapid and continues to evolve. Benefits have emerged for using DNA marks in selective breeding programs, in evaluating the contribution and effects of stocked species, and in delineating specific habitat requirements for hatchery-produced fish Purdom For managing natural populations, knowing whether the fish species exists as a single genetic unit or relatively genetically distinct groups is critical Beaumont and Hoare An additional incentive for the use of genetic tagging is that adequate tissue samples can be obtained nonlethally e.
Genetic tags are permanent and exist in all individuals, thus representing a good alternative to traditional tags. Prior to the development of DNA techniques for differentiating fish populations, investigators studied allozymes—variant enzyme forms that are coded by different alleles at the same locus or DNA sequence.
This type of genetic analysis sometimes required sacrificing fish to obtain appropriate samples, and with karyotype analysis, the examination of dividing cells was required. Small laboratory fishes such as Japanese Medaka and Zebrafish were used extensively as models for studies in vertebrate developmental genetics and for transgenic investigations Ozato and Wakamatsu Next-generation sequencing technologies rapidly obtain short DNA sequences at thousands of loci, providing a depth of potential for gathering genomic information Mardis Fisheries scientists dealing with such questions will need to update their knowledge of the appropriate, scientifically accepted genetic identification systems for their potential applications Lincoln ; Poompuang and Hallerman Stable isotopes are nonradioactive, naturally occurring forms of chemical elements that do not decay spontaneously and are generally energetically stable.
Stable isotopes of a particular chemical element differ in mass but otherwise have equivalent chemical properties. In contrast to radioisotopes, which are tightly regulated, the use of stable isotopes does not require specially approved facilities and permits. Isotope fractionation has been studied for many years in natural systems, and stable isotope ratios are now used with relative frequency for fish marking. Stable isotopes can inform studies on trophic food-web structures, feed efficiencies, fish migration and places of origin, contaminant bioaccumulation, and other physiological and ecological processes.
A variety of elements e. For obtaining fish tissues, sedation may be required see section 7. Sedatives and Related Chemicals or sacrificing may be necessary.
Depending upon the objectives of the research, nonlethal sampling may be possible by using scales, sectioned fin rays or spines, fin clips, or muscle tissue samples obtained with a small biopsy punch for stable isotope analyses.
Sampling of otoliths as metabolically inert structures is also common. Different types of metabolically active tissues have different elemental turnover rates; therefore, each investigator must determine which tissues may provide materials needed to satisfy the requirements of the studies.
Representative information on the use of stable isotopes in animal ecology has been provided by Fry and Rubenstein and Hobson In a manner similar to stable isotopes, fatty acids can be used as biomarkers to identify nutrient pathways in food webs, predator-prey relationships, and the relative contributions of allochthonous remote versus autothonous local inputs.
The use of fatty acids as biomarkers is based on the principle that fishes and many other aquatic organisms are composed of what they have eaten. Once consumed, fatty acids may be catabolized for energy or biotransformed, so the fatty acid profiles within tissues tend to reflect the dietary fatty acid profile.
Some fatty acids cannot be synthesized by vertebrates i. As mentioned for stable isotopes, various tissues have different metabolic turnover rates; thus, to be accurate, efforts linking tissue fatty acid profiles with chronological records of feeding behavior involve validation studies to account for establishing rates of profile change. For example, phospholipid profiles tend to include certain saturated fatty acids e. Traditionally, muscle and liver tissues have been used for analyses, and sacrificing the animal has been necessary.
However, adipose fin clips have shown utility for such analyses M. For more information on the role of fatty acids in aquatic ecosystems and the use of fatty acids as biomarkers, see Arts et al. Working with live fishes under laboratory conditions requires attention to many details concerning the requirements for, and limits of tolerance of, the particular species under study.
Acceptable physical facilities and an adequate supply of water with good quality must be provided, even if the fishes are to be held for only short periods of time. Although fish may tolerate marginal facilities and conditions for a few hours or even several days, holding them under less than optimal conditions will affect the results of the research.
Standards for humane treatment of animals must also be maintained, regardless of the length of time that the fishes are held. The reader should note that some content of section 7 is not restricted to laboratory activities, but may be applicable to field situations, as well.
Prior to bringing fishes into a laboratory, facilities and plans should be in place to ensure that the fish cannot escape, especially species not native to the watershed, and that the introduced fishes can be isolated physically from fishes already present. Each holding unit should have its own set of nets and other equipment. If the introduced fishes may carry disease agents, especially pathogens or parasites that are not endemic to the area, quarantine-level facilities should be used.
The level of quarantine required will vary with the seriousness of the known or suspected disease agent see section 2. Control of Pathogens and Parasites. Individual fish with suspected ill health should be quarantined from the others so as to negate the potential for spread of potential disease agents.
Such fish should be evaluated by an individual with expertise in fish diseases fish pathologist or veterinarian , and the proper therapeutant should be applied as directed. Providing guidance for the treatment of specific diseases is beyond the scope of this document. The investigator is strongly urged to establish a working relationship with individuals with expertise in fish health with whom they may consult.
Experimentation with nonindigenous fishes, transgenic fishes, or other genetically modified fishes is a special situation that requires additional precautions to preclude their escape. Permitting with site visits by state wildlife agencies may be required for holding nonindigenous species see section 3. The specific barriers may be similar to those used to prevent the escape of disease agents but must be developed to fit the physical characteristics of the laboratory or experimental facility.
The USDA has developed specifications for its own facilities and published voluntary guidelines USDA a, b intended to ensure appropriate consideration of the potential genetic and ecological effects of research activities.
These USDA guidelines a, b assist in determining appropriate procedures and safeguards so that research can be conducted without causing potentially adverse effects on the environment. Suggestions are provided for developing facility inspection guidelines and risk management procedures, appropriate locations, construction of containment structures, and nonstructural containment strategies. Institutional guidelines for working with transgenic or other genetically modified animals must be variable enough to adapt to site-specific and study-specific goals but should be sufficient to ensure that accidental release cannot occur during floods or other natural disasters or during equipment failures.
Ultimately, individual scientists are responsible for ensuring the containment of animals. Effluents from units used to hold newly introduced fishes should be treated. At a minimum, effluents should pass through screens with openings sufficiently small to retain any escaped fishes and, in turn, chemical or other treatments should be applied to kill all pathogens and parasites if they are expected to be present. Facilities conducting research on controlled disease agents see OIE lists at http: In addition, physical barriers must be in place with sufficient capacity to prevent outflow of any water in the event that all holding units are emptied USDA a, b.
Many common fish pathogens are opportunistic and are present in virtually all environments. Some are difficult to avoid e.
While the investigator can reduce problems from opportunistic pathogens by using good husbandry, the obligate pathogens must be avoided. This can be typically done by establishing an integrated fish health management plan with regular fish health inspections by appropriately qualified fish health professionals. The investigator must be aware of certain diseases and agents that are problematic in the specific geographic region where work is conducted e.
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