Cost Of Swimming Research Articles

Spatial scale and environmental determinants in minke whale habitat use and foraging

Because pelagic prey concentrations are patchy in both space and time, predators such as marine mammals require high degrees of flexibility in their habitat use. We tested the hypothesis that minke whales Balaenoptera acutorostrata adjust their habitat use during the feed- ing season at different spatial scales: their overall distribution should be determined by broad- scale oceanographic features, while foraging activity at finer scales should be dictated by short- term changes in habitat conditions. Results from generalized additive models indicate that minke whale distribution off the west coast of Scotland is dependent largely on temporally variable para- meters (sea surface temperature in spring, chlorophyll concentration in autumn), in addition to depth and topography. However, fine-scale foraging behaviour was dictated by the strength and direction of tidal currents. Seasonal distribution patterns according to environmental parameters were largely consistent between 2 different spatial scales, and over a time period of 15 yr. Signif- icantly higher sighting rates occurred in areas of predicted sandeel Ammodytes marinus presence in spring, but not during the rest of the summer, while in August and September, prey samples from the core study area consisted almost entirely of sprat Sprattus sprattus. The low energetic cost of swimming in minke whales and their ability to switch between different prey according to their seasonal availability thus appears to allow them to readily respond to temporal changes in pelagic prey concentrations at different scales. This occurs through a distribution influenced by temporally variable parameters (temperature and chlorophyll concentration), combined with adjustments in foraging activity dependent on variable conditions at fine spatial scales (tides).

The determinants of performance in master swimmers: a cross-sectional study on the age-related changes in propelling efficiency, hydrodynamic position and energy cost of front crawl

The decrease in swimming performance (v (max)) that occurs with age is a not only consequence of the physiological decrease in maximal metabolic power ([Formula: see text]) but can also be expected to depend on an increase in the energy cost of swimming (C) [Formula: see text] In turn, for a given speed and stroke C=W (d)/(η(P)η(o)) where W (d) is hydrodynamic resistance, η(P) is propelling efficiency and η(o) is overall efficiency. The aim of this study was to measure C in 47 male masters (31-85years old) swimming the front crawl at sub-maximal, aerobic, speeds. During the experiments propelling efficiency and projected frontal area (A (eff), an index of W (d)) were also determined by kinematic analysis. "Elder" masters (60-80years) swam at a significantly slower pace (0.65 vs. 0.91ms(-1)), with a lower η(P) (0.23 vs. 0.31) and a larger A (eff) (0.39 vs. 0.23m(2)) than "younger" masters (30-60years). No significant differences in C (1.45kJm(-1), on the average) were observed as a function of age or speed, but C values were significantly higher than those assessed in young elite swimmers at the very same speeds; the difference increasing with age with a rate of 0.75% per year. With the due considerations (in this study the observed changes in η(P), A (eff) and C can be either attributed to changes in speed or age) these data confirm the hypothesis that an increase in C contributes to the decrease in swimming performance that occurs with age.

The determinants of performance in master swimmers: an analysis of master world records

Human performances in sports decline with age in all competitions/disciplines. Since the effects of age are often compounded by disuse, the study of master athletes provides the opportunity to investigate the effects of age per se on the metabolic/biomechanical determinants of performance. For all master age groups, swimming styles and distances, we calculated the metabolic power required to cover the distance (d) in the best performance time as: E' maxR ¼ C d=BTP ¼ C vmax; where C is the energy cost of swimming in young elite swimmers, vmax = d/BTP is the record speed over the distance d, and BTP was obtained form "cross-sectional data" (http://www.fina.org). To establish a record performance, E' maxR must be equal to the maximal available metabolic power (E'maxA). This was calculated assuming a decrease of 1% per year at 40 - 70 years, 2% at 70 - 80 years and 3% at 80 - 90 years (as indicated in the literature) and compared to the E' maxR values, whereas up to about 55 years of age E' maxR ¼ E' maxA; for older subjects E' maxA > E' maxR; the difference increasing linearly by about 0.30% (backstroke), 1.93% (butterfly), 0.92% (front crawl) and 0.37% (breaststroke) per year (average over the 50, 100 and 200 m distances). These data suggest that the energy cost of swimming increases with age. Hence, the decrease in performance in master swimmers is due to both decrease in the metabolic power available (E' maxA) and to an increase in C.

Disrupted flow sensing impairs hydrodynamic performance and increases the metabolic cost of swimming in the yellowtail kingfish,Seriola lalandi

The yellowtail kingfish, Seriola lalandi, shows a distribution of anaerobic and aerobic (red and pink) muscle fibres along the trunk that is characteristic of active pelagic fishes. The athletic capacity of S. lalandi is also shown by its relative high standard metabolic rate and optimal (i.e. least cost) swimming speed. To test the hypothesis that lateral line afferent information contributes to efficient locomotion in an active pelagic species, the swimming performance of S. lalandi was evaluated after unilateral disruption of trunk superficial neuromasts (SNs). Unilaterally disrupting the SNs of the lateral line impaired both swimming performance and energetic efficiency. The critical swimming speed (U(crit); mean ± s.d., N=12) for unilaterally SN-disrupted fish was 2.11±0.96 fork lengths (FL) s(-1), which was significantly slower than the 3.66±0.19 FL s(-1) U(crit) of sham SN-disrupted fish. The oxygen consumption rate (mg O(2) kg(-1) min(-1)) of the unilaterally SN-disrupted fish in a speed range of 1.0-2.2 FL s(-1) was significantly greater than that of the sham SN-disrupted fish. The least gross cost of transport (GCOT; N=6) for SN-disrupted fish was 0.18±0.06 J N(-1) m(-1), which was significantly greater than the 0.11±0.03 J N(-1) m(-1) GCOT for sham SN-disrupted fish. The factorial metabolic scope (N=6) of the unilaterally SN-disrupted fish (2.87±0.78) was significantly less than that of sham controls (4.14±0.37). These data show that an intact lateral line is important to the swimming performance and efficiency of carangiform swimmers, but the functional mechanism of this effect remains to be determined.

The rising cost of warming waters: effects of temperature on the cost of swimming in fishes.

Understanding the effects of water temperature on the swimming performance of fishes is central in understanding how fish species will respond to global climate change. Metabolic cost of transport (COT)-a measure of the energy required to swim a given distance-is a key performance parameter linked to many aspects of fish life history. We develop a quantitative model to predict the effect of water temperature on COT. The model facilitates comparisons among species that differ in body size by incorporating the body mass-dependence of COT. Data from 22 fish species support the temperature and mass dependencies of COT predicted by our model, and demonstrate that modest differences in water temperature can result in substantial differences in the energetic cost of swimming.

Aerobic capacity influences the spatial position of individuals within fish schools

The schooling behaviour of fish is of great biological importance, playing a crucial role in the foraging and predator avoidance of numerous species. The extent to which physiological performance traits affect the spatial positioning of individual fish within schools is completely unknown. Schools of juvenile mullet Liza aurata were filmed at three swim speeds in a swim tunnel, with one focal fish from each school then also measured for standard metabolic rate (SMR), maximal metabolic rate (MMR), aerobic scope (AS) and maximum aerobic swim speed. At faster speeds, fish with lower MMR and AS swam near the rear of schools. These trailing fish required fewer tail beats to swim at the same speed as individuals at the front of schools, indicating that posterior positions provide hydrodynamic benefits that reduce swimming costs. Conversely, fish with high aerobic capacity can withstand increased drag at the leading edge of schools, where they could maximize food intake while possibly retaining sufficient AS for other physiological functions. SMR was never related to position, suggesting that high maintenance costs do not necessarily motivate individuals to occupy frontal positions. In the wild, shifting of individuals to optimal spatial positions during changing conditions could influence structure or movement of entire schools.

Dramatic effect of pop-up satellite tags on eel swimming

The journey of the European eel to the spawning area in the Sargasso Sea is still a mystery. Several trials have been carried out to follow migrating eels with pop-up satellite tags (PSATs), without much success. As eels are very efficient swimmers, tags likely interfere with their high swimming efficiency. Here we report a more than twofold increase in swimming cost caused by a regular small satellite tag. The impact was determined at a range of swimming speeds with and without tag in a 2-m swimming tunnel. These results help to explain why the previous use of PSATs to identify spawning sites in the Sargasso Sea was thus far unsuccessful.

B21 水泳中の異なる呼吸様式が浮力のモーメントに与える影響(水中運動の解析と計測)

The purpose of this study was to examine if the escalation of leg-sinking effect of buoyancy around the center of mass (CM) during breathing changes due to different breathing patterns -- chest breathing and abdominal breathing. Five male participated in this study. The positions of the CM, the position of the center of volume (CV), and distance between CM and CV were determined. The results showed that CV-CM distance increased for 1.47cm with chest breathing and for 0.94cm with abdominal breathing. As a result of these change of distance, the leg-sinking effect increase for 10.27Nm with chest breathing and for 6.40Nm with abdominal breathing. The small leg-sinking effect decrease the energy cost of swimming. The results of this study indicates that abdominal breathing reduces the leg-sinking effect of buoyancy, suggesting that abdominal breathing may improve the performance of swimming.

Estimated field metabolic rates and prey requirements of resident killer whales

AbstractKiller whales are large animals that often feed in groups and thus have the potential to deplete prey populations. Determining predator energy requirements is essential to assessing whether prey availability is sufficient. This is important because one risk factor facing the endangered Southern Resident killer whale distinct population segment is limited prey availability. Body mass, field metabolic rate (FMR), and daily prey energy requirements (DPERs) were estimated for each individual in the population. FMRs were calculated from body mass, assuming they range from five to six times Kleiber‐predicted basal metabolic rates. FMRs of adults were also calculated from resident killer whale activity budgets and the metabolic cost of swimming at speeds associated with daily activities. These two methods yielded similar results. Total FMRs varied by age and sex, which is partly due to the long developmental period and sexual dimorphism in killer whales. FMRs for males (465–4,434 kg) ranged from 35,048 to 228,216 kcal/d while FMRs for females (465–3,338 kg) ranged from 35,048 to 184,444 kcal/d. DPERs were calculated from FMRs assuming a standard digestive efficiency. Corresponding DPERs ranged from 41,376 to 269,458 kcal/d and 41,376 to 217,775 kcal/d, respectively.

Can filter‐feeding Asian carp invade the Laurentian Great Lakes? A bioenergetic modelling exercise

Summary1. There is much concern that filter‐feeding Asian carp will invade the Laurentian Great Lakes and deplete crucial plankton resources. We developed bioenergetic models, using parameters from Asian carp and other fish species, to explore the possibility that planktonic food resources are insufficient to support the growth of silver carp (Hypophthalmichthys molitrix) and bighead carp (H. nobilis) in the Great Lakes.2. The models estimated basic metabolic requirements of silver and bighead carp under various body sizes, swimming speeds and reproductive stages. These requirements were then related to planktonic food resources and environmental temperature to predict when and where silver and bighead carp may survive in the Great Lakes, and how far they may travel.3. Parameter values for respiration functions were derived experimentally in a coordinated study of silver and bighead carp, while consumption parameters were obtained from the literature on silver carp. Other model parameters lacking for Asian carp, such as those for egestion and excretion, were obtained from the literature on other fish species.4. We found that full‐sized bighead carp required 61.0 kJ d−1 just to maintain their body mass at 20 °C, approximately equivalent to feeding in a region with 255 μg L−1 macrozooplankton (dry) or 10.43 μg L−1 chlorophyll a. Silver carp energy requirements were slightly higher.5. When applied to various habitats in the Great Lakes, our results suggest that silver and bighead carp will be unable to colonise most open‐water regions because of limited plankton availability. However, in some circumstances, carp metabolism at lower temperatures may be low enough to permit positive growth even at very low rations. Positive growth is even more likely in productive embayments and wetlands, and the modelled swimming costs in some of these habitats suggest that carp could travel >1 km d−1 without losing biomass.6. The simulation (and firmly hypothetical) results from this modelling study suggest when and where Asian carp could become established in the Great Lakes. Given the potential consequences to Great Lakes ecosystems if these filter feeders do prove capable of establishing reproducing populations, efforts to keep Asian carp out of the Great Lakes must not be lessened. However, we do encourage the use of bioenergetic modelling in a holistic approach to assessing the risk of Asian carp invasion in the Great Lakes region.

The effects of swimming pattern on the energy use of gilthead seabream (Sparus aurata L.)

Oxygen consumption () was measured for gilthead seabream (Sparus aurata) during spontaneous and forced activities. During spontaneous activity, the swimming pattern was analysed for the effect on on the average speed (U), turning rate (θ) and change in speed (ΔU). All swimming characteristics contributed significantly to the source of spontaneous swimming costs, and the models explained up to 58% of the variation in Prediction of of fish in field studies can thereby be improved if changes in speed and direction are determined in addition to swimming speed. A relationship between swimming speed and during forced activity was also established. During spontaneous activity, 2.5 times more energy was used than in forced swimming at a speed of 0.5 BL s−1. This indicates that spontaneous swimming costs may be considerably higher compared with those of a fixed swimming speed. However, comparing at the respective optimum swimming speeds with the lowest cost of transport (U opt) resulted in similar values independent of swimming mode. This could be an important observation in estimating energetic costs of free-ranging fishes.

Partition of aerobic and anaerobic swimming costs related to gait transitions in a labriform swimmer

Members of the family Embiotocidae exhibit a distinct gait transition from exclusively pectoral fin oscillation to combined pectoral and caudal fin propulsion with increasing swimming speed. The pectoral-caudal gait transition occurs at a threshold speed termed U(p-c). The objective of this study was to partition aerobic and anaerobic swimming costs at speeds below and above the U(p-c) in the striped surfperch Embiotoca lateralis using swimming respirometry and video analysis to test the hypothesis that the gait transition marks the switch from aerobic to anaerobic power output. Exercise oxygen consumption rate was measured at 1.4, 1.9 and 2.3 L s(-1). The presence and magnitude of excess post-exercise oxygen consumption (EPOC) were evaluated after each swimming speed. The data demonstrated that 1.4 L s(-1) was below the U(p-c), whereas 1.9 and 2.3 L s(-1) were above the U(p-c). These last two swimming speeds included caudal fin propulsion in a mostly steady and unsteady (burst-assisted) mode, respectively. There was no evidence of EPOC after swimming at 1.4 and 1.9 L s(-1), indicating that the pectoral-caudal gait transition was not a threshold for anaerobic metabolism. At 2.3 L s(-1), E. lateralis switched to an unsteady burst and flap gait. This swimming speed resulted in EPOC, suggesting that anaerobic metabolism constituted 25% of the total costs. Burst activity correlated positively with the magnitude of the EPOC. Collectively, these data indicate that steady axial propulsion does not lead to EPOC whereas transition to burst-assisted swimming above U(p-c) is associated with anaerobic metabolism in this labriform swimmer.

FIRST IN THE MEASURE OF ENERGETICS IN A SWIMMING TETRAPOD

![Figure][1] Gerald Kooyman discusses Henry Prange and Knut Schmidt-Nielsen's 1970 paper entitled: ‘The metabolic cost of swimming in ducks.’ A copy of the paper can be obtained from What is the nature of a classic paper? It

When foraging becomes unprofitable: energetics of diving in tidal currents by common eiders wintering in the Arctic

A variety of ecological, physiological and environmental factors influence the energy budgets of diving animals. For common eiders Somateria mollissima sedentaria wintering in sea ice habitats in the Canadian Arctic, time and energy costs of diving increase exponentially with tidal cur- rent speed. Here we use literature estimates of diving energetics and underwater dive data to quan- titatively model net energy gain per dive cycle as a function of current speed. The model indicates a strong non-linear decrease in the profitability of diving with increasing currents, predicting that net energy gain per dive cycle will reach zero and become unprofitable at 1.21 m s -1 (at 11.3 m depth using baseline parameters from our study). As currents increase travel time, foraging time at the bot- tom decreases non-linearly, reaching a point where intake is inadequate to balance increasing div- ing and surface swimming costs. Sensitivity analysis indicates that this threshold is robust over a range of energy expenditure rates and is influenced most by energy intake rate, emphasising the importance of ecological factors such as prey abundance and quality. Eiders stop foraging and rest on the ice well below this threshold in weaker current regimes (~0.8 m s -1 ), at about the point when prof- itability begins to decelerate. Behavioural time series of diving under constraints of strong tidal cur- rent regimes indicate that these eiders do occasionally dive in currents up to ~1.2 m s -1 , providing support for the energetic model. Eiders did not dive in faster currents, which could also be influenced by a physiological limit to swimming speed. We conclude that ocean currents can cause a non-linear decrease in net energy balance and are therefore an important and understudied consideration for diving animals. Many functional aspects of diving (e.g. locomotor costs or convective heat loss) have non-linear characteristics; these diminishing returns can be expected to play an important role in the dynamics of behavioural routines and the ability of organisms to respond to environmental variation.

The influence of temperature and light on larval pre-settlement metamorphosis: a study of the effects of environmental factors on pre-settlement metamorphosis of the solitary ascidian Styela canopus

This study investigated the effects of two environmental factors, temperature and light, on larval settlement and metamorphosis in the solitary ascidian Styela canopus. The results revealed that larval settlement rates decreased with increasing temperature in the range 12–30°C. We also demonstrated for the first time that pre-settlement metamorphosis of ascidian larvae can occur as a function of temperature. We suggest this could be an adaptation to avoid the greater energetic cost of active larval swimming, presumably resulting from the increasing temperature. They are able to metamorphose into passive drifting post-larvae and to continue planktonic life. This finding has implications for larval dispersal, especially under conditions of ocean warming. In addition, the effect of light intensity on larval settlement and metamorphosis was significantly different between photoperiods of 24 L : 0 D and 12 L : 12 D. These results provide some insight into the complex cues affecting settlement and metamorphosis of ascidian larvae and ascidian distribution in nature.

Postprandial metabolic increment of southern bluefin tuna Thunnus maccoyii ingesting high or low‐lipid sardines Sardinops sagax

This study examined the postprandial metabolism and swimming speed of southern bluefin tuna Thunnus maccoyii when fed sardines Sardinops sagax of either high-lipid and high-energy content or low-lipid and low-energy content. Five groups of two or three T. maccoyii (mean+/-s.e. mass=19.8+/-0.5 kg, n=14) were fed either low [2.2% lipid, 5.5 MJ kg(-1) gross energy (GE)] or high-lipid (12.9%, 9.2 MJ kg(-1) GE) S. sagax. Before feeding, T. maccoyii swam at 0.74+/-0.03 body lengths s(-1) (n=5) and their routine metabolic rate was 305+/-15 mg kg(-1) h(-1). Swimming speed and metabolic rate of T. maccoyii increased following feeding. Thunnus maccoyii swam 1.3 and 1.8 times faster during digestion of low and high-lipid S. sagax, respectively. Postprandial peak metabolic rate, duration of elevated metabolism and total postprandial metabolic increment were all greater for T. maccoyii that ingested high-lipid S. sagax. When total postprandial increment is represented as a proportion of ingested energy, there was no difference between high and low-lipid meals, equating to between 30 and 35% of ingested energy. It was estimated that increased postprandial swimming costs account for 25 and 46% of the total postprandial metabolic response for low and high-lipid S. sagax meals, respectively. Specific dynamic action (SDA) accounts for c. 20% of ingested energy regardless of S. sagax lipid level. These results confirm that the postprandial metabolic increment of T. maccoyii is greater than most other fish species. Much of the high cost of postprandial metabolic increment can be attributed to increased postprandial swimming costs. For T. maccoyii, it appears that activity and SDA are not independent, which complicates bioenergetic evaluation. High postprandial metabolic costs accentuate the great energetic requirements of T. maccoyii.

The effects of acute temperature change on cost of transport at maximal labriform speed in bluegill Lepomis macrochirus

The effects of acute temperature change on the cost of bluegill Lepomis macrochirus swimming were quantified. At 14 degrees C, maximum labriform swimming speed (U(lab,max)) was reduced relative to that at the acclimation temperature of 22 degrees C, but total cost of transport (T(TC)) remained unchanged. At 30 degrees C, U(lab,max) was the same as at 22 degrees C, but T(TC) was 66% greater.

Prey abundance, channel structure and the allometry of growth rate potential for juvenile trout

Abstract The application of a drift‐foraging bioenergetic model to evaluate the relative influence of prey abundance (invertebrate drift) and habitat (e.g. pool frequency) on habitat quality for young‐of‐the‐year (YOY) and yearling juvenile cutthroat trout, Oncorhynchus clarki (Richardson) is described. Experiments and modelling indicated simultaneous limitation of fish growth by prey abundance and habitat, where depth and current velocity limit the volume of water and prey flowing through a fish’s reactive field as well as swimming costs and prey capture success. Predicted energy intake and growth increase along a depth gradient, with slower deeper pool habitat generating higher predicted growth for both YOY and yearling trout. Bioenergetic modelling indicated that fish are constrained to use progressively deeper habitats to meet increasing energy requirements as they grow. Sensitivity of growth to prey abundance identified the need to better understand how variation in invertebrate drift and terrestrial drop affects habitat quality and capacity for drift‐feeding fishes.

Aerobic Cost in Elite Female Adolescent Swimmers

Maximal performance in swimming depends on metabolic power and the economy of swimming. Thus, the energy cost of swimming (economy= VO(2)/V, C(s)) and maximal aerobic power (VO(2max)) in elite young female swimmers (n=10, age: 15.3+/-1.5 years) and their relationships to race times (50-1,000 m) and national ranking were examined. VO(2) increased exponentially with velocity (V), (VO(2)=5.95+(-10.58 V)+5.84 V(2)) to a maximal VO(2) of 2.71+/-0.50 L x min(-1) (46.7+/-8.2 mL x kg(-1) x min(-1)) at a free swimming velocity of 1.37+/-0.07 m x s(-1). C(s) was constant up to 1.2 m x s(-1) (21.5 mL x m(-1)), however was significantly higher at 1.36 m x s(-1) (27.3 mL x m(-1)). Peak [La] was 5.34+/-2.26 mM. C(s) expressed as a percentage of Cs at maximal swimming velocity was significantly correlated with race times and ranking across a number of distances. The data for these elite females demonstrate that the energy cost of swimming is a good predictor of performance across a range of distances. However, as swimming performance is determined by a combination of factors, these findings warrant further examination.

Longitudinal Development of Physical and Performance Parameters during Biological Maturation of Young Male Swimmers

The aim of the study was to examine the development of specific physical, physiological, and biomechanical parameters in 29 young male swimmers for whom measurements were made three times for two consecutive years. During the 400-m front-crawl swimming, the energy cost of swimming, and stroking parameters were assessed. Peak oxygen consumption (VO2 peak) was assessed by means of the backward-extrapolation technique recording VO2 during the first 20 sec. of recovery period after a maximal trial of 400-m distance. Swimming performance at different points of physical maturity was mainly related to the increases in body height and arm-span values from physical parameters, improvement in sport-specific VO2 peak value from physiological characteristics, and improvement in stroke indices on biomechanical parameters. In addition, biomechanical factors characterised best the 400-m swimming performance followed by physical and physiological factors during the 2-yr. study period for the young male swimmers.