scholarly journals Serendipitous observations from animal-borne video loggers reveal synchronous diving and equivalent simultaneous prey capture rates in chinstrap penguins

2021 ◽  
Vol 168 (8) ◽  
Author(s):  
Jefferson T. Hinke ◽  
Tamara M. Russell ◽  
Victoria R. Hermanson ◽  
Laura Brazier ◽  
Stephanie L. Walden
Keyword(s):  
Foraging Behavior ◽  
Prey Capture ◽  
Group Formation ◽  
Euphausia Superba ◽  
Video Observation ◽  
Diving Behavior ◽  
Behavioral Repertoire ◽  
Visual Contact ◽  
Total Consumption ◽  
Capture Rates

AbstractSeabirds often engage in coordinated, cooperative foraging to improve detection and capture of prey. An extreme example of such coordinated behavior is synchronicity, whereby the movements of individuals are aligned temporally and spatially. Synchronous diving among penguins has been reported, but simultaneous observations of predation by synchronously diving individuals have not. We instrumented chinstrap penguins (Pygoscelis antarcticus) during their incubation period in December 2019 from Cape Shirreff, Livingston Island, Antarctica (60.79°W, 62.46°S) with video and depth recorders to monitor predator foraging behavior and prey consumption rates. Serendipitously, two instrumented individuals, accompanied by a third, banded individual, engaged in synchronous foraging activities on Antarctic krill (Euphausia superba) for 9.25 h. This group formed ashore, transited together to their foraging area, remained in close visual contact after dives, synchronously timed diving behavior, and foraged at similar depths. Prey capture rates were positively correlated across dives and total consumption estimates were equivalent for the two instrumented birds during the video observation period. Video loggers confirmed that synchronous diving and foraging behavior are among the behavioral repertoire of chinstrap penguins and demonstrated equivalent prey capture rates by synchronously foraging predators. The results further suggest that group formation while ashore and group cohesion during a foraging trip may facilitate shared foraging success among group members.

Whole body withdrawal circuit and its involvement in the behavioral hierarchy of the mollusk Clione limacina

1996 ◽  
Vol 75 (2) ◽  
pp. 529-537 ◽  
Author(s):  
T. P. Norekian ◽  
R. A. Satterlie
Keyword(s):  
Feeding Behavior ◽  
Motor Neurons ◽  
Prey Capture ◽  
The Body ◽  
Whole Body ◽  
High Threshold ◽  
Behavioral Repertoire ◽  
Withdrawal Behavior ◽  
Cerebral Neurons ◽  
Clione Limacina

1. The behavioral repertoire of the holoplanktonic pteropod mollusk Clione limacina includes a few well-defined behaviors organized in a priority sequence. Whole body withdrawal takes precedence over slow swimming behavior, whereas feeding behavior is dominant over withdrawal. In this study a group of neurons is described in the pleural ganglia, which controls whole body withdrawal behavior in Clione. Each pleural withdrawal (Pl-W) neuron has a high threshold for spike generation and is capable of inducing whole body withdrawal in a semi-intact preparation: retraction of the body-tail, wings, and head. Each Pl-W neuron projects axons into the main central nerves and innervates all major regions of the body. 2. Stimulation of Pl-W neurons produces inhibitory inputs to swim motor neurons that terminate swimming activity in the preparation. In turn, Pl-W neurons receive inhibitory inputs from the cerebral neurons involved in the control of feeding behavior in Clione, neurons underlying extrusion of specialized prey capture appendages. Thus it appears that specific inhibitory connections between motor centers can explain the dominance of withdrawal behavior over slow swimming and feeding over withdrawal in Clione.

An Experimental Analysis of Macrophyte Growth Forms as Fish Foraging Habitat

1991 ◽  
Vol 48 (1) ◽  
pp. 123-131 ◽  
Author(s):  
Michele Dionne ◽  
Carol L. Folt
Keyword(s):  
Plant Growth ◽  
Growth Form ◽  
Plant Density ◽  
Prey Capture ◽  
Capture Rate ◽  
Habitat Associations ◽  
Growth Forms ◽  
Plant Growth Form ◽  
Macrophyte Growth ◽  
Capture Rates

In this laboratory study we measured the independent effects of macrophyte growth form, plant density, and prey abundance on the foraging rate of the pumpkinseed sunfish (Lepomis gibbosus). We demonstrate that macrophyte growth forms are not all similar in their effects on fish foraging. Prey capture rates of pumpkinseeds foraging among Scirpus validus (cylindrical stems) were 53 and 365% times greater than for Potamogeton amplifolius (leafy stems) for cladoceran (Sida crystallina) and larval damselfly (Coenagrionidae) prey, respectively. Plant growth form influenced prey capture rates more than charges in natural plant density. Plant density effects ranged from none on damselfly capture rates to a 29% decline in cladoceran capture rate over a twofold increase in plant density. Our results indicate that in plant-structured habitats, variation in plant growth form can be an important determinant of fish foraging and habitat associations.

Effects of cadmium on the foraging behavior and growth of juvenile bluegill, Lepomis macrochirus

1995 ◽  
Vol 52 (8) ◽  
pp. 1630-1638 ◽  
Author(s):  
Miehael D. Bryan ◽  
Gary J. Atchison ◽  
Mark B. Sandheinrich
Keyword(s):  
Foraging Behavior ◽  
Standardized Test ◽  
Prey Capture ◽  
Prey Size ◽  
Cadmium Concentration ◽  
Control Level ◽  
Lepomis Macrochirus ◽  
Aquatic Organisms ◽  
Handling Time ◽  
Behavioral Measure

Standardized test protocols for assessing chemical hazards to aquatic organisms inadequately consider behavioral effects of toxicants; yet, organisms behaving abnormally in the wild have reduced growth, reduced fitness, and high mortality. We determined the chronic effects of cadmium (0, 30, 60, 120, and 240 μg∙L−1) on juvenile bluegill (Lepomis macrochirus) foraging behavior and growth rates in functional response experiments, each using different sized Daphnia as prey. Bluegill consumption rate increased with prey density. Cadmium-exposed fish initially attacked fewer prey per unit of time than unexposed fish, with subsequent recovery to control-level consumption rates determined by cadmium concentration and prey size. The degree of change (over time) in the number of Daphnia attacked per 30 s was the most consistently sensitive behavioral measure of sublethal stress in exposed bluegill; the lowest observed effect concentration (LOEC) was 37.3 μg Cd∙L−1. Effects on prey attack rates (attacks/30 s) were inversely related to prey size; cadmium had the greatest effect on bluegill foraging on the smallest prey. Cadmium had no effect on prey capture efficiency or handling time. Growth in bluegill length and weight was reduced (P ≤ 0.019) by all cadmium concentrations and was a more sensitive end point than were the foraging behaviors.

Effects of the trematode Microphallus turgidus on locomotion and prey capture in the grass shrimp Palaemonetes pugio

2003 ◽  
Vol 77 (4) ◽  
pp. 327-330 ◽  
Author(s):  
R.N. Khan ◽  
J.A. Spiers ◽  
O.J. Pung
Keyword(s):  
Intermediate Host ◽  
East Coast ◽  
Prey Capture ◽  
Grass Shrimp ◽  
Palaemonetes Pugio ◽  
Growth And Survival ◽  
Data Support ◽  
The Usa ◽  
Host Behaviour ◽  
Capture Rates

AbstractThe grass shrimp, Palaemonetes pugio, is common in estuaries and marshes along the east coast of the USA and is frequently infected with metacercariae of the trematode, Microphallus turgidus. To test whether or not M. turgidus has an effect on intermediate host behaviour, the length of time spent swimming and walking over 1 min and 3 min intervals and prey (Artemia) capture rates of uninfected grass shrimp and those infected with 1–10, 11–20 or 21–30 metacercarial cysts were compared. Uninfected shrimps spent significantly more time swimming than infected shrimps during the first minute of observation. There were no differences between the control and infected groups in terms of swimming at 3 min, walking at 1 and 3 min, or in numbers of prey captured. These results indicate that M. turgidus may induce little or no change in grass shrimp locomotion nor in prey capture behaviour. This is in contrast to other parasites that modify intermediate host behaviour to enhance their transmission to definitive hosts. Furthermore, these data support earlier studies indicating that M. turgidus does not affect the growth and survival of P. pugio.

Determination of prey capture rates in the stony coral Galaxea fascicularis: a critical reconsideration of the clearance rate concept

2011 ◽  
Vol 92 (4) ◽  
pp. 713-719 ◽  
Author(s):  
Ronald Osinga ◽  
Sanne Van Delft ◽  
Muhammad Wahyudin Lewaru ◽  
Max Janse ◽  
Johan A.J. Verreth
Keyword(s):  
Clearance Rate ◽  
Prey Item ◽  
Prey Capture ◽  
Capture Efficiency ◽  
Accurate Estimation ◽  
Surrounding Water ◽  
Galaxea Fascicularis ◽  
Feeding Experiments ◽  
Total Capture ◽  
Capture Rates

In order to determine optimal feeding regimes for captive corals, prey capture by the scleractinian coral Galaxea fascicularis was determined by measuring clearance of prey items from the surrounding water. Colonies of G. fascicularis (sized between 200 and 400 polyps) were incubated in 1300 ml incubation chambers. Nauplii of the brine shrimp Artemia sp. were used as the prey item. A series of incubation experiments was conducted to determine the maximal capture per feeding event and per day. To determine maximal capture per feeding event, total uptake of nauplii after one hour was determined for different prey item availabilities ranging from 50 to 4000 nauplii per polyp. To determine maximal capture per day, the corals were subjected to four repetitive feeding events at three different prey item densities (50, 100 and 150 nauplii per polyp). Alongside these quantitative experiments, it was tested to what extent the feeding response of corals is triggered by chemical cues. One hour after food addition, extract of Artemia nauplii was added to the incubation chambers to test its effect on subsequent prey capture rates. In all experiments, prey capture was expressed as the number of nauplii consumed per coral polyp. Total capture of Artemia nauplii by G. fascicularis after a single feeding event increased linearly up till a prey item availability of 2000 nauplii per polyp. Maximal capture per feeding event was estimated at 1200 nauplii per polyp, which is higher than rates reported in previous studies. It became apparent that at high densities of Artemia nauplii, the clearance rate method does not discriminate between active capture and passive sedimentation. Repetitive feeding with 50 nauplii per polyp resulted in a constant total prey capture per feeding event. At a supply of 100 nauplii per polyp, total capture decreased after the first feeding event, and remained constant during the subsequent feeding events at a level comparable to the lower food availability. However, at a supply of 150 nauplii per polyp, total capture per event was higher throughout the entire four-hour incubation period, which obfuscates an accurate estimation of the maximal daily food uptake. In all incubations, a decrease in capture efficiency was observed within the course of the feeding event. In all repetitive feeding experiments, capture efficiency increased immediately upon addition of a new batch of food. This increase in efficiency was not caused by a priming effect of extract of Artemia. The inconsistencies in the data show that estimates of prey capture based on clearance rates should be interpreted with caution, because this method does not take into account potential dynamics of prey capture and release.

scholarly journals Initial Feeding Behaviour, Eye Structure and Effect of Colours on Prey Capture Rates of Betta splendens Larvae

2015 ◽  
Vol 10 (5) ◽  
pp. 357-366 ◽  
Author(s):  
Nivaldo Ferreira do Nascimento ◽  
Fernanda Nogueira Valentin ◽  
Matheus Pereira-Sa ◽  
Sheryll Yohana Corch Chavarro ◽  
Breno Manzini ◽  
...  
Keyword(s):  
Feeding Behaviour ◽  
Prey Capture ◽  
Betta Splendens ◽  
Capture Rates

Sub-ice foraging behavior of emperor penguins

2000 ◽  
Vol 203 (21) ◽  
pp. 3275-3278 ◽  
Author(s):  
P.J. Ponganis ◽  
R.P. Van Dam ◽  
G. Marshall ◽  
T. Knower ◽  
D.H. Levenson
Keyword(s):  
Foraging Behavior ◽  
Prey Capture ◽  
Video Camera ◽  
Foraging Strategy ◽  
Video Technology ◽  
Emperor Penguins ◽  
Behavioral Studies ◽  
Pagothenia Borchgrevinki ◽  
The Mean ◽  
Underwater Video Camera

Emperor penguins (Aptenodytes forsteri) were equipped with a remote underwater video camera, the Crittercam, to evaluate sub-ice foraging behavior while the birds dived from an isolated dive hole. Three birds dived and foraged successfully for 1 h periods after being trained to wear and to dive with a harness for camera attachment. Video and depth profile recordings revealed that emperor penguins travel at shallow depths (<50 m), ascend to the undersurface of the ice to feed on fish, and descend back to depth to return to the exit hole. Although the mean durations of dives of individual birds with the Crittercam were 21–35 % shorter than the diving durations of these same birds without the camera, the dive profiles in both situations were similar, thus demonstrating a similar foraging strategy in birds diving without the camera. Despite shorter diving durations with the camera, the penguins were still successful at prey capture in 80 % of 91 dives greater than 1 min in duration. Prey included the sub-ice fish Pagothenia borchgrevinki. Hunting ascents (from depth to within 5 m of the surface) occurred in 85 % of dives, ranged from zero to three per dive, and were associated with successful prey capture in 77 % of 128 ascents. Occasionally, several fish were captured during a single ascent. These observations and this application of video technology create a model for further physiological and behavioral studies of foraging, and also emphasize the potential importance of shallow dives as sources of food intake for emperor penguins during foraging trips to sea.

scholarly journals Is Heightened-Shoaling a Good Candidate for Positive Emotional Behavior in Zebrafish?

Animals ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 152 ◽  
Author(s):  
Becca Franks ◽  
Courtney Graham ◽  
Marina von Keyserlingk
Keyword(s):  
Social Dynamics ◽  
Single Case ◽  
Emotional Behavior ◽  
Diving Behavior ◽  
Future Research ◽  
Behavioral Repertoire ◽  
Affiliative Behavior ◽  
Video Clips ◽  
Shoaling Behavior ◽  
Fish Tank

Zebrafish, a highly-social species of freshwater fish, are widely studied across many fields of laboratory science including developmental biology, neuroscience, and genomics. Nevertheless, as standard housing for zebrafish typically consists of small and simplistic environments, less is known about their social behavioral repertoire in more naturalistic settings. In particular, spontaneously occurring, socio-positive affiliative behaviors (e.g., social coordination and cohesion) that may be indicative of positive emotional experiences have rarely been reported or studied deliberately in zebrafish. Housing adult zebrafish (10 fish/tank) in large semi-natural tanks (110 L; n = 6) with sloping gravel substrate, rocks, and artificial plants, we observed a previously undescribed behavior: Distinct periods of spontaneous, synchronized, compact aggregations, what we call “heightened-shoaling”. This project aimed to quantify the characteristics of this distinctive behavior and compare parameters of heightened-shoaling to baseline periods (normal behavior) and pre-feed periods (feed-anticipatory behavior). First, across 4 days, we selected video-clips (100 s each) from within (i) instances of heightened-shoaling (n = 9), (ii) baseline periods (n = 18), and (iii) pre-feed periods (n = 18). For each of these video clips, we scan sampled every 10 s to determine fish orientations and location within the tank and agonistic behavior. Next, we used an all-occurrence sampling method to record the timing and duration of all episodes of heightened-shoaling behavior when tank-lights were on (8:00 h to 18:00 h) across 10 days. From the scan-sampling data, we found that compared to baseline periods, heightened-shoaling was characterized by increased shoal cohesion (p < 0.0001), increased adherence to the horizontal plane (p < 0.0001), decreased agonism (p < 0.0001), and no diving behavior (lower positions within the water column signal negative effect in zebrafish, p > 0.1). From the all-occurrence sampling data, we found 31 episodes of heightened-shoaling with instances observed in all six tanks and only a single case in which heightened-shoaling occurred in two tanks at the same time. The median episode duration was 7.6 min (Range 1.3–28.6). As the first systematic description of heightened-shoaling behavior, this research contributes to our knowledge of the range of zebrafish social dynamics living in naturalistic environments. Moreover, as a spontaneously occurring, protracted, affiliative behavior, heightened-shoaling appears to be a good candidate for future research into positive emotional behavior in zebrafish.

The Food Searching Behaviour of Two European Thrushes. Ii: the Adaptiveness of the Search Patterns

Behaviour ◽  
1974 ◽  
Vol 49 (1-2) ◽  
pp. 1-60 ◽  
Author(s):  
James N.M. Smith
Keyword(s):  
Prey Capture ◽  
Average Length ◽  
Temporal Variations ◽  
High Density ◽  
Behavioural Plasticity ◽  
Low Density ◽  
Searching Behaviour ◽  
Artificial Food ◽  
Spatial Changes ◽  
Capture Rates

Abstract1) This study describes the searching behaviour of two thrushes foraging for both naturally occurring and artificial foods. I have paid particular attention to temporal and spatial changes in searching behaviour and have attempted to answer the question of whether the changes in searching behaviour were adaptive ones. 2) When thrushes captured an earthworm and continued searching, they showed a net change in patterning of the twelve turns following capture so that they probably searched the area surrounding the capture point more thoroughly than an area covering the same number of moves units before capture (Figs 4, 5; Table 1). This confirms N. TINBERGEN'S (1967) hypothesis that path changes sometimes follow prey capture in bird predators. Since earthworms on the study meadow were aggregated in distribution, the net change in path may have been of adaptive value to the thrushes, by concentrating their search where further prey items were most likely to occur. It was not, however, possible to relate the increased searching effort quantitatively to the size of the earthworm aggregates. (3) The thrushes were then presented with populations of cryptically-coloured artificial prey in random, regular and aggregated distributions at each of two densities (Fig. 7). The movements of the thrushes (mainly blackbirds) feeding on these prey were recorded as described by SMITH (1974). (4) The overall distribution of the search paths of the thrushes showed a correspondence with the distributions of the artificial food populations (Fig. 9). The thrushes made larger turns and showed less tendency to alternate left and right turns at the higher density (Tables 8, 11), thus helping them to maintain their search paths within the smaller confines of the high density populations. (5) The capture rates of the thrushes at the two prey densities were roughly proportional to the differences in prey density (Table 4). Although there were suggestions of differing capture rates, unforeseen errors in experimental procedure did not allow firm conclusions on the effects of thrush predation on the different prey distributions within each density. (6) The presentation of the cryptic artificial prey led to an increase in the average length of moves made by blackbirds (Fig. 10; Table 5). Further increases in move length followed the cutting of the grass on the study meadow (Fig. 13) and the introduction of more conspicuous artificial prey (Figs 11, 12). It is suggested that the increases in move lengths were an adaptive reaction by the blackbirds to increases in prey detectability. (7) Captures of single artificial prey were preceded by larger than average turns and were followed by larger than average turns in the opposite direction (Table 9). (8) The presentation of the artificial food led to an overall increase in the speed of movement of the blackbirds (Table 10). (9) After the capture of prey in the low density random and aggregated populations thrushes showed a net tendency to concentrate their searching in the area surrounding the site of prey capture (Fig. 16; Table 12), similar to that shown after the capture of earthworms. This was not shown after the capture of regularly distributed prey (Figs 16, 17 ; Table 12), nor was it clearly shown after the capture of prey in the high density random and aggregated distributions (Fig. 17; Table 12). (10) The overall speed of movement was greater over the ten moves preceding capture than over the ten moves following capture in the low density regular distribution (Table 13). (11) The changes in searching behaviour following capture are discussed with reference to N. TINBERGEN'S (1967) hypothesis that predators select for 'spacing out' in prey. (12) A method is presented which allowed the measurement of the wild blackbirds' abilities to detect the artificial prey supplied (Figs 18-20). The 'risk' to the artificial prey was high when the blackbirds were within 20 cm of the prey, but fell to near zero at a distance of 120 cm. (Fig. 21). The square root of the risk was linearly related to the distance between predator and prey (Fig. 22). The measures of the detection ability of the blackbirds are discussed in relation to their movement patterns. (13) The results are discussed in light of the general problem of whether predatory animals show adaptive flexibility in response to spatial and temporal variations in food supply. I have argued that at least some aspects of the thrushes' behaviour provide evidence for such flexibility. I have emphasised that the basic 'unpredictability' of the environment, which generates the need for behavioural plasticity, also makes it unrealistic to expect to find predators making optimally adapted responses to all variations in the environment.

Sign in / Sign up

Export Citation Format

Share Document