Prey Behavior, Age‐Dependent Vulnerability, and Predation Rates

Susan Lingle; Alex Feldman; Mark S. Boyce; W. Finbarr Wilson

doi:10.1086/591675

The influence of benthic tundra pond vegetation and prey behavior on Zooplankton predation by the flatworm Mesostoma lingua

Canadian Journal of Zoology ◽

10.1139/z85-239 ◽

1985 ◽

Vol 63 (7) ◽

pp. 1617-1621 ◽

Cited By ~ 8

Author(s):

Hugh J. MacIsaac ◽

Thomas C. Hutchinson

Keyword(s):

Daphnia Pulex ◽

Chironomus Riparius ◽

Alternative Prey ◽

Prey Behavior ◽

Predation Rates ◽

Branchinecta Paludosa

Experiments were conducted at the Smoking Hills and Tuktoyaktuk, N.W.T., to determine if Mesostoma lingua, a common pond inhabitant, preys selectively on co-occurring Zooplankton, and whether predation rates are affected by the presence of pond vegetation. Experiments were conducted in 250-mL containers at the sites. Mesostoma fed heavily on Daphnia pulex and Chironomus riparius, but not on Branchinecta paludosa or Diaptomus arcticus. The presence of alternative prey led to significant reductions in Daphnia predation rates, while the presence of the pond plants Cladophora insignis and Drepanocladus aduncus, which provide shelter and cover, significantly increased predation rates. The advantage of the moss and algal habitat was largely to the predator.

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Role of satiation in the functional response of a piscivore, largemouth bass (Micropterus salmoides)

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f99-289 ◽

2000 ◽

Vol 57 (3) ◽

pp. 548-556 ◽

Cited By ~ 21

Author(s):

Timothy E Essington ◽

James R Hodgson ◽

James F Kitchell

Keyword(s):

Functional Response ◽

Largemouth Bass ◽

Consumption Rate ◽

Micropterus Salmoides ◽

Sustainable Consumption ◽

Stomach Fullness ◽

Daily Consumption ◽

Prey Behavior ◽

Natural Settings ◽

Predation Rates

We evaluated whether satiation regulates the predation rates of a piscivore, largemouth bass (Micropterus salmoides), in natural settings. A functional response model indicated that predation rates can be reduced by satiation when mean prey density is high or when prey encounters are highly patchy. We then used bioenergetics modeling to estimate the predation rates of individual bass in four lakes during a 16-year period and used stomach content mass in diet samples to evaluate the variability in daily predation rates. Predation rates, expressed as the proportion (p) of the maximum daily consumption rate, were low (mode = 0.3, mean = 0.4). Stomach fullness (s), expressed as the proportion of the stomach fullness associated with the maximum sustainable consumption rate, was highly variable, and 13% of all bass diets had s > 1, indicating that bass could opportunistically forage at rates exceeding their maximum sustainable rate. The low predation rates and the ability to consume prey at rates exceeding the maximum sustainable rate make it unlikely that satiation was an important constraint on bass predation rates. Thus, satiation effects widely represented in modeling studies may be a rare component in piscivore-prey interactions, while prey behavior may be a more important component governing predation rates.

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A laboratory study of the feeding behavior of the rhabdocoel Mesostoma ehrenbergii on pond Cladocera

Canadian Journal of Zoology ◽

10.1139/z82-176 ◽

1982 ◽

Vol 60 (6) ◽

pp. 1305-1307 ◽

Cited By ~ 23

Author(s):

Steven S. Schwartz ◽

Paul D. N. Hebert

Keyword(s):

Feeding Behavior ◽

Laboratory Study ◽

Size Dependent ◽

Prey Behavior ◽

Cladoceran Species ◽

Predation Rates

The predation rates of the rhabdocoel Mesostoma ehrenbergii were determined on a number of cladoceran species. Two means of capturing prey are employed by the flatworm but only active predation was explored in these experiments. It was found that this flatworm is a size-dependent predator with a preference for prey of about 1.2 mm. It was also observed that prey behavior was not an important factor in determining susceptibility to predation. M. ehrenbergii is a voracious predator; individuals consume more than 10 prey/day.

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Effects of Hyperoxia on Lung Utrastructure

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100067121 ◽

1970 ◽

Vol 28 ◽

pp. 26-27

Author(s):

Gladys Harrison

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Light Microscopy ◽

Oxygen Effects ◽

Age Dependent ◽

The Central Nervous System ◽

The Subject ◽

Space Age ◽

Alveolar Septa ◽

Extensive Damage

With the advent of the space age and the need to determine the requirements for a space cabin atmosphere, oxygen effects came into increased importance, even though these effects have been the subject of continuous research for many years. In fact, Priestly initiated oxygen research when in 1775 he published his results of isolating oxygen and described the effects of breathing it on himself and two mice, the only creatures to have had the “privilege” of breathing this “pure air”.Early studies had demonstrated the central nervous system effects at pressures above one atmosphere. Light microscopy revealed extensive damage to the lungs at one atmosphere. These changes which included perivascular and peribronchial edema, focal hemorrhage, rupture of the alveolar septa, and widespread edema, resulted in death of the animal in less than one week. The severity of the symptoms differed between species and was age dependent, with young animals being more resistant.

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