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PubMedDate not supplied

Predation of Biomphalaria glabrata during the development of Belostoma anurum (Hemiptera, Belostomatidae).

Belostoma anurum was reared under laboratory conditions. Specimens were exposed to semi-natural conditions of photo period. The mortality rate was 26.3% during the post embryonic period (38.6 +/- 0.7 days). During this time the average predation of Biomphalaria glabrata was of 99.0 +/- 9.4 snails. The mean increment ratio of length and dry weight per instar was of 1.4 +/- 0.1 and 2.8 +/- 0.5, respectively. The predation by B. anurum adults can be divided into two different periods: phase I (4.8 +/- 1.4 snails/day) and phase II (1.8 +/- 0.5 snails/day). The higher predation in phase I suggested the sexual maturation of the belostomatid.

Animals↗
PubMed2002

Predation potential of the water bugs Sphaerodema rusticum on the sewage snails Physa acuta.

The sewage snail Physa acuta is a serious threat to certain economic plants and to the purification plant of sewage works by rendering the biofilters ineffective. Various attempts are being made to control it. The efficacy of the predacious water bugs Sphaerodema rusticum was judged experimentally, in the laboratory in the potential control of P. acuta. It is revealed that, when supplied separately, the first, second and third instar and the adult S. rusticum did not attack P. acuta belonging to 3.1-8 mm, 5.1-8 mm, 7.1-8 mm and </= 3 mm size classes respectively. In the remaining trials predation rate varied from zero to eight (average 2.3) individuals per predator per day. In experiments with P. acuta belonging to all the size classes supplied together, none, except the first instar S. rusticum, attacked the prey individuals belonging to the lowest (</= 3 mm) size class. The first and second instar S. rusticum, in both trials did not attack P. acuta larger than 4 mm and 5 mm in shell length respectively. The water bugs belonging to the third, fourth, fifth instar and adult stages though preyed upon P. acuta with 3.1-8 mm shell length. The average rate of predation by a single S. rusticum varied from 0.14-3.08 individuals per day depending upon the size of P. acuta and the stage of S. rusticum. A single S. rusticum, irrespective of instar and adult stages, destroyed on average 4.16 P. acuta daily irrespective of sizes. It is estimated that one S. rusticum could destroy 1,360 P. acuta in its life time. The results clearly indicate that the water bug S. rusticum may be used to control the snails P. acuta.

Analysis of Variance↗
PubMed2003

Water mite predation on zooplankton of a tropical lake.

Water mite (Krendowskia sp.) predation on zooplanktonic species from Lake Monte Alegre (São Paulo State, Brazil) was tested in laboratory experiments. One cladoceran, Daphnia gessneri, two copepods, Tropocyclops prasinus and Thermocyclops decipiens, and Chaoborus larvae III and IV were supplied as prey to adult mites. The cladoceran Ceriodaphnia cornuta was used in the experiment with mite nymphs. Only D. gessneri was preyed on by mites, at an average rate of 7 ind./mite/day, at 23-24 degrees C. Although Chaoborus was not eaten by the predator in the experiment, in direct observations older larvae were seen to be seized by several mites, both predators and prey sinking to the bottom of the vessel. Adult Daphnia was grabbed by its dorsal side, swimming together with the mite. There was an increase in predatory activity two hours after sunset.

Animals↗
PubMed2005

Effect of sub-lethal concentrations of permethrin on ovary activation in the predator Supputius cincticeps (Heteroptera: Pentatomidae).

Insecticides may cause mortality and deleterious effects on predatory stinkbugs. For this reason, the effect of five concentrations of permethrin applied on third instar nymphs of Supputius cincticeps (Stål) (Heteroptera: Pentatomidae) was investigated on ovary activation in this predator. The nymphs received topical application of permethrin in the following concentrations (mg a.i./ml): 10(-7), 10(-6), 10(-5), 10(-4), and 10(-3). Ovary lengths and oocyte numbers were quantified following first egg mass. Ovary length of S. cincticeps varied from 5.7 mm with 10(-4) mg a.i./ml, to 6.4 mm with 10(-7) mg a.i./ml, with similar values for the other permethrin concentrations and for the control. The number of oocytes per female varied from 13.5 with 10(-3) mg a.i./ml, to 29.2 for the control, with significant differences. The number of oocytes per female of nymphs exposed to a permethrin concentration of 10(-5) mg a.i./ml was similar to that of the control. However, the lower number of oocytes per female from nymphs exposed to other concentrations of permethrin suggests that this insecticide may affect the reproductive capacity of this predator. The results obtained are discussed in relation to tolerance of Heteroptera predators to insecticides and possible hormesis occurrence.

Animals↗
PubMed2000

Performance of a pyrethroid-resistant strain of the predator mite Typhlodromus pyri (Acari: Phytoseiidae) under different insecticide regimes.

An organophosphate pyrethroid-resistant strain of Typhlodromus pyri Scheuten imported from New Zealand was reared on potted apple trees in an outdoor insectary. From 1988 to 1995, the population was selected one to three times per year with a dilute solution (1.7 ppm) of the pyrethroid cypermethrin. Petri dish bioassays with cypermethrin in 1995 indicated that the insectary-reared T. pyri had an LC50 of 81 ppm versus 0.006 ppm for native T. pyri taken from a research orchard. The bioassays suggested that recommended orchard rates of cypermethrin would cause heavy mortality in native populations of T. pyri but only moderate losses in the imported New Zealand strain. Bioassays in 1996 with the organophosphate insecticide dimethoate indicated both New Zealand and native T. pyri were susceptible and that recommended orchard rates of dimethoate likely would cause high mortality of T. pyri in apple orchards. These findings from bioassays were supported by data from orchard trials. In June and July 1993, insectary-reared New Zealand T. pyri were placed on five apple trees in each of eight 38-tree plots in the research orchard. In late August 1994, New Zealand T. pyri from orchard trees that had been sprayed twice by airblast sprayer with the full recommended rate of 50 g (AI)/ha (83 ppm) cypermethrin were placed on the other 33 trees in each of six plots. In the summers of 1994-1996, plots were treated with one of the following insecticide regimes: (1) conventional integrated pest management (IPM) (registered neurotoxic insecticides considered harmless or slightly toxic to T. pyri); (2) advanced IPM (use of newer, more selective insecticides); (3) pyrethroid (at least one full-rate application of cypermethrin); (4) dimethoate; and (5) dimethoate plus pyrethroid. Densities of European red mite, Panonychus ulmi (Koch), were highest in all plots treated with dimethoate and in pyrethroid plots not yet inoculated with New Zealand T. pyri. Densities of apple rust mite, Aculus schlechtendali (Nalepa), and of the stigmaeid predator Zetzellia mali (Ewing) were highest in plots treated with dimethoate and were nearly absent in the IPM plots. Densities of T. pyri were high enough for effective biocontrol in the IPM plots and in the pyrethroid plots 1-2 yr after release of the New Zealand strain, provided pyrethroid was applied just before the resistant strain was released in the orchard. A recurring theme of this study was the generally negative association between densities of phytophagous mites and those of T. pyri, suggesting the ability of this predator to suppress their prey. In contrast, the positive association between phytophagous mites and Z. mali suggests the inability of this predator to regulate their prey at least under the conditions of this study.

Animals↗
PubMed2004

Influence of cover crops on insect pests and predators in conservation tillage cotton.

In fall 2000, an on-farm sustainable agricultural research project was established for cotton, Gossypium hirsutum L., in Tift County, Georgia. The objective of our 2-yr research project was to determine the impact of several cover crops on pest and predator insects in cotton. The five cover crop treatments included 1) cereal rye, Secale cereale L., a standard grass cover crop; 2) crimson clover, Trifolium incarnatum L., a standard legume cover crop; 3) a legume mixture of balansa clover, Trifolium michelianum Savi; crimson clover; and hairy vetch, Vicia villosa Roth; 4) a legume mixture + rye combination; and 5) no cover crop in conventionally tilled fields. Three main groups or species of pests were collected in cover crops and cotton: 1) the heliothines Heliothis virescens (F.) and Helicoverpa zea (Boddie); 2) the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois); and 3) stink bugs. The main stink bugs collected were the southern green stink bug, Nezara viridula (L.); the brown stink bug, Euschistus servus (Say); and the green stink bug, Acrosternum hilare (Say). Cotton aphids, Aphis gossypii Glover, were collected only on cotton. For both years of the study, the heliothines were the only pests that exceeded their economic threshold in cotton, and the number of times this threshold was exceeded in cotton was higher in control cotton than in crimson clover and rye cotton. Heliothine predators and aphidophagous lady beetles occurred in cover crops and cotton during both years of the experiment. Geocoris punctipes (Say), Orius insidiosus (Say), and red imported fire ant, Solenopsis invicta Buren were relatively the most abundant heliothine predators observed. Lady beetles included the convergent lady beetle, Hippodamia convergens Guérin-Méneville; the sevenspotted lady beetle, Coccinella septempunctata L.; spotted lady beetle, Coleomegilla maculata (DeGeer); and the multicolored Asian lady beetle, Harmonia axyridis (Pallas). Density of G. punctipes was higher in cotton fields previously planted in crimson clover compared with control cotton fields for all combined sampling dates in 2001. Intercropping cotton in live strips of cover crop was probably responsible for the relay of G. punctipes onto cotton in these crimson clover fields. Density of O. insidiosus was not significantly different between cover crop and control cotton fields. Lady beetles seemed to relay from cover crops into cotton. Conservation of the habitat of fire ants during planting probably was responsible for the higher density of red imported fire ants observed in all conservation tillage cotton fields relative to control cotton fields. Reduction in the number of times in which economic thresholds for heliothines were exceeded in crimson clover and rye compared with control fields indicated that the buildup of predaceous fire ants and G. punctipes in these cover crops subsequently resulted in reduction in the level of heliothines in conservation tillage cotton with these cover crops compared with conventional tillage cotton without cover crops.

Agriculture↗
PubMed2005

Effects of dispersal, predators (Acari: Phytoseiidae), weather, and ground cover treatments on populations of Tetranychus urticae (Acari: Tetranychidae) in apple orchards.

In a 2-yr study of causes of mite outbreaks in apple (Malus spp.) orchards in Nova Scotia, we monitored immigration of Tetranychus urticae Koch from orchard ground cover into trees populated by the generalist phytoseiid predator Typhlodromus pyri Scheuten. In both years, T. urticae-days in the tree canopy increased with number of T. urticae caught in sticky bands on tree trunks. In 2000, T. urticae-days were negatively correlated with T. pyri-days. Lack of correlation in 2001 was attributed to higher rates of immigration, which would mask the effects of predation. Weather also affected mite dynamics. Rainfall in July and August was less in 2001 than in 2000. Heat units were sufficient for six generations of T. urticae in 2001 but only for five in 2000. Consequently, T. urticae-days in the tree canopy and immigration rates were significantly greater in 2001 than in 2000, despite three-fold greater use of miticides. We also tested the effects of herbicides on T. urticae immigration. Application of selective herbicides in laneways reduced coverage of reproductive hosts of T. urticae, but these changes did not reduce immigration. In 2001, application of a miticidal herbicide, glufosinate, in tree rows reduced captures of T. urticae on sticky bands in high immigration orchards but not in low immigration orchards. We conclude that generalist predators and modified herbicide use are insufficient remedies and that effective biological control of T. urticae in the ground cover by a specialist phytoseiid such as Amblyseius fallacis Garman is essential to prevent outbreaks.

Acari↗
PubMed2006

Rapid, high-throughput detection of azalea lace bug (Hemiptera: Tingidae) predation by Chrysoperla rufilabris (Neuroptera: Chrysopidae), using fluorescent-polymerase chain reaction primers.

Azalea lace bugs, Stephanitis pyrioides (Scott) (Hemiptera: Tingidae), are the most common pest of azaleas (Rhododendron spp.) in nursery production and the landscape. Although pesticides are commonly used to control lace bugs, natural enemies can be a significant source of lace bug mortality. Lacewings (Neuroptera: Chrysopidae) are natural enemies of lace bugs and easily consume them in laboratory studies. Field studies on lacewing biocontrol of azalea lace bugs are underway; however, monitoring lacewing predation in a nursery environment by direct observation is impractical. Here, we describe a fluorescent-polymerase chain reaction method to estimate S. pyrioides consumption based on the gut contents of lacewing predators. Lace bug DNA was detected in fed lacewings up to 32 h after ingestion. More than 80% of the ingested lace bugs were detected using our method with only one false positive result. The assay is both high-throughput and relatively inexpensive, making it a practical approach to documenting lace bug predation in the field.

Animals↗
PubMed2006

Effects of larval competitors and predators on oviposition site selection of Anopheles gambiae sensu stricto.

We examined whether predators and competitors influence selection of oviposition sites by Anopheles gambiae Giles. Mosquitoes in cages laid significantly fewer eggs in rainwater conditioned with a predator (backswimmers, Notonecta sp.) than in unconditioned rainwater. Rainwater conditioned with a putative competitor (tadpoles, Xenopus sp.) also had fewer eggs than unconditioned rainwater. Similarly, mosquitoes laid significantly fewer eggs in rainwater conditioned with five and 50 An. gambiae larvae than in unconditioned rainwater. When larvae were present, significantly more eggs were laid in containers with five larvae than in containers with higher densities, but the differences in number of eggs laid were not significant among the densities of 40, 70, and 100 larvae. This study demonstrated that caged An. gambiae females avoid oviposition in habitats with supposed competitors and predators.

Analysis of Variance↗
PubMed2006

Plant facilitation of a belowground predator.

Interest in facilitative predator plant interactions has focused upon above-ground systems. Underground physical conditions are distinctive, however, and we provide evidence that bush lupine, Lupinus arboreus, facilitates the survival of the predatory nematode Heterorhabditis marelatus. Because H. marelatus is prone to desiccation and lupines maintain a zone of moist soil around their taproots even during dry periods, we hypothesized that dry-season nematode survival under lupines might be higher than in the surrounding grasslands. We performed field surveys and measured nematode survival in lupine and grassland rhizospheres under wet- and dry-season conditions. Nematodes survived the crucial summer period better under lupines than in grasslands; however, this advantage disappeared in wet, winter soils. Modeling the probability of nematode population extinction showed that, while even large nematode cohorts were likely to go extinct in grasslands, even small cohorts in lupine rhizospheres were likely to survive until the arrival of the next prey generation. Because this nematode predator has a strong top-down effect on lupine survival via its effect on root-boring larvae of the ghost moth Hepialus californicus, this facilitative interaction may enable a belowground trophic cascade. Similar cases of predator facilitation in seasonally stressful environments are probably common in nature.

Animals↗
PubMed2006

Adding infection to injury: synergistic effects of predation and parasitism on amphibian malformations.

We explored the importance of interactions between parasite infection and predation in driving an emerging phenomenon of conservation importance: amphibian limb malformations. We suggest that injury resulting from intraspecific predation in combination with trematode infection contributes to the frequency and severity of malformations in salamanders. By integrating field surveys and experiments, we evaluated the individual and combined effects of conspecific attack and parasite (Ribeiroia ondatrae) infection on limb development of long-toed salamanders (Ambystoma macrodactylum). In the absence of Ribeiroia, abnormalities involved missing digits, feet, or limbs and were similar to those produced by cannibalistic attack in experimental trials. At field sites that supported Ribeiroia, malformations were dominated by extra limbs and digits. Correspondingly, laboratory exposure of larval salamanders to Ribeiroia cercariae over a 30-day period induced high frequencies of malformations, including extra digits, extra limbs, cutaneous fusion, and micromelia. However, salamander limbs exposed to both injury and infection exhibited 3-5 times more abnormalities than those exposed to either factor alone. Infection also caused significant delays in limb regeneration and time-to-metamorphosis. Taken together, these results help to explain malformation patterns observed in natural salamander populations while emphasizing the importance of interactions between parasitism and predation in driving disease.

Ambystoma↗
PubMed1993

The impact of predators on livestock in the Abruzzo region of Italy.

Free-living populations of wolves (Canis lupus Linnaeus, 1758) and brown bears (Ursus arctos Linnaeus, 1758) regularly cause damage to livestock in the Abruzzo region of Italy. The laws of the region provide for compensation payments to owners for losses caused by predators. In the present paper, 4,993 validated claims made between 1980 and 1988 are examined. Losses ascribed to wolf, bear and wild boar attacks were 92.1%, 7.8% and 0.1%, respectively, of the total losses caused by predators during this period. The victims of wolf attacks were mostly sheep and goats (45.0%) and equids (38.5%), followed by cattle (16.4%) and rabbits, fowl and dogs (0.2%). Bears also principally attacked sheep and goats (67.6%), other targets being cattle (18.5%), equids (9.5%) and bee-hives (4.4%). A significant difference was observed between the number of attacks by wolves and bears; although both populations are of similar size. Other statistically significant differences have been observed between the periods in which the attacks take place on the different livestock and the predator species which reportedly caused the damage. Among cattle and equids, victims are mostly new-born or young animals, while among sheep and goats only adult animals are attacked.

Animals↗
PubMed2002

Predator-induced behavioral and morphological plasticity in the tropical marine Gastropod Strombus gigas.

Florida queen conch stocks once supported a significant fishery, but overfishing prompted the state of Florida to institute a harvest moratorium in 1985. Despite the closure of the fishery, the queen conch population has been slow to recover. One method used in the efforts to restore the Florida conch population has been to release hatchery-reared juvenile conch into the wild; however, suboptimal predator avoidance responses and lighter shell weights relative to their wild counterparts have been implicated in the high mortality rates of released hatchery juveniles. We conducted a series of experiments in which hatchery-reared juvenile conch were exposed to a predator, the spiny lobster (Panulirus argus), to determine whether they could develop behavioral and morphological characteristics that would improve survival. Experiments were conducted in tanks with a calcareous sand substrate to simulate a natural environment. Conditioned conch were exposed to caged lobsters while conch in the control tanks were exposed to empty cages. Conditioned conch moved significantly less and buried themselves more frequently than the naive control conch. Morphometric data indicated that the conditioned conch grew at a significantly slower rate than the naive conch, but the shell weights of the two groups were not significantly different. This implies that the conditioned conch had thicker or denser shells than the control group. As a result, the conditioned conch had significantly higher survival than naive conch in a subsequent predation experiment in which a lobster was allowed to roam free in each tank for 24 hours. In the future, the conditioning protocols documented in this study will be used to increase the survival of hatchery-reared conch in the wild.

Animals↗
PubMed1999

Biomass control in waste air biotrickling filters by protozoan predation.

Two protozoan species as well as an uncharacterized protozoan consortium were added to a toluene-degrading biotrickling filter to investigate protozoan predation as a means of biomass control. Wet biomass formation in 23.6-L reactors over a 77-day period was reduced from 13.875 kg in a control biotrickling filter to 11.795 kg in a biotrickling filter enriched with protozoa. The average toluene vapor elimination capacity at 1 g/m3 toluene and 64 m3/(m3. h) was 31.1 g/(m3. h) in the control and 32.2 g/(m3. h) in the biotrickling filter enriched with protozoa. At higher toluene inlet concentrations, toluene degradation rates increased and were slightly higher in the biotrickling filter enriched with protozoa. The lower rate of biomass accumulation after the addition of protozoa was due to an increase of carbon mineralization (68% as compared to 61% in the control). Apparent biomass yield coefficients in the control and enriched trickling filter were 0.72 and 0.59 g dry biomass/g toluene, respectively. The results show that protozoan predation may be a useful tool to control biomass in biotrickling filters, however, further stimulation of predation of the biomass immobilized in the reactor is required to ensure long-term stability of biotrickling filters.

Air Pollutants↗
PubMed1999

Mosquito and aquatic predator communities in ground pools on lands deforested for rice field development in central Sulawesi, Indonesia.

Aquatic habitats, mosquitoes, and larvivorous predators were studied on deforested lands in Central Sulawesi, Indonesia. Open ground pools, mainly in depressions made by the treads of bulldozers and other heavy equipment, were numerous but because of their small size, comprised ca. 1% or less of the total area of the deforested lands studied. The dominant mosquitoes in these pools were Anopheles vagus, Culex vishnui, Culex tritaeniorhynchus, and Culex gelidus. The 1st 2 species were dominant in clear pools, whereas the latter 2 species were dominant in turbid pools. The dominant metazoans other than mosquitoes were Crustacea, Ephemeroptera, and Chironomidae. Both aquatic and surface predators were abundant. Dominant among aquatic predators were Anisoptera and Zygoptera nymphs, Dytiscidae, and Notonectidae. These results are discussed in relation to mosquito control on deforested lands that transitionally but inevitably appear during the course of rice field development projects in Indonesia.

Agriculture↗
PubMedDate not supplied

[Predators, resources, and trophic chains in the regulation of plankton population and biomass in oligothrophic lakes].

The relative strength of "top-down" versus "bottom-up" control of plankton community structure and biomass in two small oligotrophic lakes (with and without fish), located near the Polar circle (Russia), has been investigated for two years, 1996 and 1997. The comparative analyses of zooplankton biomass and species abundance showed strong negative effect of fish, stickeback (Pungitius pungitius L.), on the zooplankton community species, size structure and biomass of particular prey species but no effect on the biomass of the whole trophic level. An intensive predation in Verkhneye lake has lead to: 1) sixfold decline in biomass of large cladoceran Holopedium gibberum comparing to the lake lacking predator, 2) shift in the size mode in zooplankton community and the replacement of the typical large grazers by small species--Bosmina longirostris and rotifers. Their abundance and biomass even increased, demonstrating the stimulating effect of fish on the "inefficient" and unprofitable prey organisms. The analysis of contributions of different factors into the cladoceran's birth rate changes was applied to demonstrate the relative impact of predators and resources on zooplankton abundance. An occasional introduction of the stickleback to Vodoprovodnoye lake (the reference lake in 1996) in summer 1997 lead to drastic canges in this ecosystem: devastating decrease of zooplankton biomass and complete elimination of five previously dominant grazer species. The abundance of edible phytoplankton was slightly higher in the lake with fish in 1996 and considerably higher in the lake where fish has appeared in 1997 showing the prevailing "top-down" control of phytoplankton in oligotrophic ecosystem. The reasons of trophic cascade appearance in oligotrophic lakes are also discussed.

Animals↗
PubMed2001

Neurotoxic lesions of the lateral nucleus of the amygdala decrease conditioned fear but not unconditioned fear of a predator odor: comparison with electrolytic lesions.

Considerable evidence suggests that the lateral (LA) and basal (BA) nuclei of the amygdala are sites of plasticity and storage of emotional memory. Recent arguments, however, have seriously challenged this view, suggesting that the effects of amygdala lesions are attributable to interference with performance of fear behavior and not learning and memory. One way to address this controversy is to measure the same behavioral response during both conditioned and unconditioned fear. This is done in the present study by measuring fear-related freezing behavior after electrolytic and neurotoxic lesions of the LA or LA/BA nuclei in rats in a contextual fear conditioning paradigm and unconditioned fear to a predator odor. Electrolytic LA lesions attenuated post-shock freezing, retention test freezing, and freezing to the predator odor trimethylthiazoline (TMT). In contrast, excitotoxic NMDA lesions of the LA had no effect on post-shock freezing but significantly attenuated retention test freezing. Furthermore, excitotoxic LA lesions did not diminish freezing to TMT. Larger excitotoxic lesions that included the BA significantly reduced freezing in both the post-shock and retention tests but did not appreciably decrease freezing to TMT. The results suggest that the LA is important for memory of learned fear but not for generation of freezing behavior. In addition, the BA plays a role in freezing in conditioned fear situations but not in unconditioned fear. The studies suggest that the LA and BA play different roles in fear conditioning, but neither of them has a significant role in unconditioned freezing to a predator odor.

Amygdala↗
PubMed2002

The importance of the gut and its contents in prey as a source of cadmium to predators.

Many mammalian and avian predators consume the whole carcass of their small mammal prey. Thus, the contaminant load of the gut and its contents may be of toxicological significance, but pollutant loads in the gut of prey species are often not measured and their role in food-chain transfer of contaminants is largely unquantified. We investigated the importance of the gut and its contents in prey as a source of cadmium (Cd) to predators by measuring the Cd concentrations in the guts (including contents), in various body tissues, and in the intact bodies of wood mice (Apodemus sylvaticus). The mice had been fed for up to 365 d on either control, a medium-Cd (MCd) diet, or a high-Cd (HCd) diet that had nominal Cd concentrations of 0, 8, and 40 g/g wet weight, respectively. In wood mice fed contaminated diets, Cd was progressively bioaccumulated in all the body tissues that were analyzed. The gut (and contents) and the liver and kidneys (the critical organs) contained most of the accumulated Cd and were the only significant contributors to the total body burden (TBB). The contribution of the gut (and contents) to the TBB was greater in mice fed MCd diet than in those given HCd feed but declined with age (equivalent to exposure duration) in both groups as Cd in the critical organs increasingly became the most important source of TBB Cd. However, the gut and its contents contributed between 50 and 100% of the Cd TBB in mice fed for up to six months on MCd diet; this was the diet that most closely mimicked the estimated average Cd intake of wood mice on contaminated sites. The results of this study highlight the importance of including measures of Cd load in the gut when modeling food-chain transfer from small mammals to their predators.

Animals↗