Bioenergetics of salmonid fishes: Energy intake, expenditure and productivity

1 Time and energy are key currencies in animal ecology, and judicious management of these is a primary focus for natural selection At present, however, there are only two main methods for estimation of rate of energy expenditure in the field, heart rate and doubly labelled water, both of which have been used with success; but both also have their limitations 2 The deployment of data loggers that measure acceleration is emerging as a powerful tool for quantifying the behaviour of free-living animals Given that animal movement requires the use of energy, the accelerometry technique potentially has application in the quantification of rate of energy expenditure during activity 3 In the present study, we test the hypothesis that acceleration can serve as a proxy for rate of energy expenditure in free-living animals We measured rate of energy expenditure as rates of O2 consumption (VO2) and CO2 production (VCO2) in great cormorants (Phalacrocorax carbo) at rest and during pedestrian exercise VO2 and VCO2 were then related to overall dynamic body acceleration (ODBA) measured with an externally attached three-axis accelerometer 4 Both VO2 and VCO2 were significantly positively associated with ODBA in great cormorants This suggests that accelerometric measurements of ODBA can be used to estimate VO2 and VCO2 and, with some additional assumptions regarding metabolic substrate use and the energy equivalence of O2 and CO2, that ODBA can be used to estimate the activity specific rate of energy expenditure of free-living cormorants 5 To verify that the approach identifies expected trends in from situations with variable power requirements, we measured ODBA in free-living imperial cormorants (Phalacrocorax atriceps) during foraging trips We compared ODBA during return and outward foraging flights, when birds are expected to be laden and not laden with captured fish, respectively We also examined changes in ODBA during the descent phase of diving, when power requirements are predicted to decrease with depth due to changes in buoyancy associated with compression of plumage and respiratory air 6 In free-living imperial cormorants, ODBA, and hence estimated VO2, was higher during the return flight of a foraging bout, and decreased with depth during the descent phase of a dive, supporting the use of accelerometry for the determination of activity-specific rate of energy expenditure

Moving towards acceleration for estimates of activity-specific metabolic rate in free-living animals: the case of the cormorant

Oogenesis in fishes follows a universal plan; yet, due to differences in the synchrony and rate of egg development, spawning frequency varies from daily to once in a lifetime. Some species spawn and feed in separate areas, during different seasons, by storing energy and drawing on it later for reproduction (i.e. capital breeding). Other species spawn using energy acquired locally, throughout a prolonged spawning season, allocating energy directly to reproduction (i.e. income breeding). Capital breeders tend to ovulate all at once and are more likely to be distributed at boreal latitudes. Income breeding allows small fish to overcome allometric constraints on egg production. Income breeders can recover more quickly when good-feeding conditions are re-established, which is a benefit to adults regarding bet-hedging spawning strategies. Many species exhibit mixed capital- and income-breeding patterns. An individual's position along this capital–income continuum may shift with ontogeny or in relation to environmental conditions, so breeding patterns are a conditional reproductive strategy. Poor-feeding environments can lead to delayed maturation, skipped spawning, fewer spawning events per season or fewer eggs produced per event. In a few cases, variations in feeding environments appear to affect recruitment variability. These flexible processes of energy acquisition and allocation allow females to prioritize their own condition over their propagules' condition at any given spawning opportunity, thereby investing energy cautiously to maximize lifetime reproductive value. These findings have implications for temporal and spatial sampling designs, for measurement and interpretation of fecundity, and for interpreting fishery and ecosystem assessments.

/pdf/energy-acquisition-and-allocation-to-egg-production-in-331aqp6cge.pdf

Energy acquisition and allocation to egg production in relation to fish reproductive strategies

FROM the time of its appearance half a century ago, Jordan and Everyman's "Fishes of North and Middle America"has until to-day remained the only comprehensive descriptive account of the fishes of the western Atlantic Ocean. Much new knowledge has become available during this long period, and the time is now ripe for a new and up-to-date publication covering approximately the same field. The appearance of Volume 1 of "Fishes of the Western North Atlantic" is therefore most welcome and will supply a much-felt need. This volume, the first of a projected series, brings to fruition the. initial part of a plan conceived in New Haven a considerable time ago. With the establishment of the Sears Foundation for Marine Research at Yale University in, 1937, funds became available for publication on auite an ambitious scale, and a group of expert ichthyologists met to discuss the preparation of a work such as is now appearing. Fishes of the Western North Atlantic Part 1: Lancelets, by Henry B. Bigelow Isabel Perez Paufante; Cyclostomes, by Henry B. Bigelow and William C. Schroeder; Sharks, by Henry B. Bigelow and William C. Schroeder. (Sears Foundation for Marine Research, Memoir No. 1.) Pp. xvii+576. (New Haven, Conn.: Yale University, 1948.) 10 dollars.

Fishes of the Western North Atlantic

Fishes of the Gulf of Maine

Energy expended in migration and reproduction was determined from measurements of caloric concentration and body and gonodal weight for nontrophic sea lampreys collected from different sites along the St. John River, New Brunswick. The estimated cost of locomotion in swimming the 140 km which separates the estuary from the spawning redds was 300 and 260 kcal for males and females respectively. Acutal distance which lampreys swam as well as mean swimming speed were estimated from a linear regression equation relating energy expenditure for locomotion and body weight. Energy expenditure for breeding was considerably greater than that catabolized throughout the upstream migration.

Migration and spawning energetics of the anadromous sea lamprey, Petromyzon marinus

Oxygen consumption of juvenile walleye increased between 5 and 15°C at each swimming speed between 20 and 45 cm s−1. With further increase in temperature to 23.5°C, oxygen consumption declined. Basal oxygen consumption was estimated by extrapolation of the relationship between swimming speed and the logarithm of oxygen consumption to 0 cm s−1. The metabolic cost of swimming, represented by the difference between total and basal oxygen consumption was independent of temperature at each swimming speed. Energy required to swim 1 km increased from 2.14 to 5.68 J g−1 between 20 and 45 cm s−1.

Swimming metabolism and temperature in juvenile walleye,Stizostedion vitreum vitreum

Larval, metamorphosing and adult representatives of the southern brook lamprey,Ichthyomyzon gagei, were collected from Choclafaula Creek in Alabama to provide information on aspects of its life cycle. The proportional length of the prebranchial, branchial, trunk and tail regions changed throughout larval life in a pattern similar to that demonstrated in other lampreys. Body depth changed also throughout much of larval life. Oral disc, dorsal fin height, and eye diameter increased through all or most of metamorphosis and the adult interval. Length-frequency curves for larvae indicate a larval life of 3 1/4–4 1/4 years. Growth rate, reflected by change in total length, was constant throughout the year for each age group. Sex ratio of larvalI. gagei was 1♂: 1.02♀. Metamorphosis is initiated in early September and is completed between early February and mid March. Adult 1. gagei spawn between mid April and early May. The number of oocytes ranged from 820–2485 between 95–150 mm total length. The maximum gonadosomic ratio in males was 17.1 and 26.3% in females.

https://link.springer.com/content/pdf/10.1007%2FBF00005566.pdf

Biology of the southern brook lamprey, Ichthyomyzon gagei

Basal and swimming oxygen consumption of juvenile lake charr (8 and 12°C and walleye (8°C) were measured for fish exposed either to a natural or constant photoperiod. Seasonal changes in oxygen consumption were not demonstrable at the basal level or for swimming at comparable speeds between 20 and 45 cm s−1. The absence of a seasonal change in oxygen consumption among juvenile fish is in marked contrast to the seasonal pattern described in other studies at the basal and active level in mature fish.

Metabolism and photoperiod in juvenile lake charr and walleye

Metamorphosis of the nonparasitic mountain brook lamprey, I. greeleyi, is described within 7 phases based on external morphological changes. The commencement of metamorphosis in early August is consistent with the pattern for northern hemisphere lampreys which display an inverse relationship with latitude. The sequence of external changes including the development of eyes, oral disc, teeth, tongue, oral fimbriae and lateral line its consistent among individuals of I. greeleyi and lampreys in general. Some of the changes realized during metamorphosis of I. greeleyi are important to the adult period while others reflect their presumed parasitic ancestry. Energy reserves by nonfeeding I. greeleyi during the 104–140 days required to complete metamorphosis are replaced by water so that total length and body weight do not change significantly during this time.

H. Beamish

Papers

Migration and spawning energetics of the anadromous sea lamprey, Petromyzon marinus

Swimming metabolism and temperature in juvenile walleye,Stizostedion vitreum vitreum

Biology of the southern brook lamprey, Ichthyomyzon gagei

Metabolism and photoperiod in juvenile lake charr and walleye

Metamorphosis of the mountain brook lamprey Ichthyomyzon greeleyi