Intraguild Predation Research Articles

Intraguild predation of Phenacoccus manihoti parasitoid Anagyrus lopezi by two mealybug predators, Cryptolaemus montrouzieri and Plesiochrysa ramburi

Anagyrus lopezi is a specialist parasitoid was introduced to Indonesia in 2014 to control cassava mealybug, Phenacoccus manihoti. Plesiochrysa ramburi and Cryptolaemus montrouzieri are generalist predator insects associated with the mealybug. Intraguild predation is a crucial competition in an insect community. The study objective was to investigate interference of both predators on healthy mealybug (unparasitized) or parasitized mealybug by A. lopezi (mealybug which containing parasitoid larvae 1-, 3-, 8-, and 14-day old). Experiments were carried out in a non-choice test (served only one unparasitized or parasitized mealybug of a specific parasitoid age) and choice test (unparasitized and parasitized mealybug of a specific parasitoid age together) in laboratory under controlled environmental conditions. Both of predators species able to fed on both unparasitized and parasitized mealybugs of three different age (1-, 3-, and 8- day-old), but both predators discriminated against mealybug were parasitized 14-day old (hardened mummies). Interaction between parasitoid of A. lopezi and both predators showed antagonistic interaction type. We recommended A. lopezi should be released in field at the beginning of the time when the population of the mealybug is still low and could be continued with the predators release when the mealybug population is high.

On the Origins of Phenotypic Parallelism in Benthic and Limnetic Stickleback.

Rapid evolution of similar phenotypes in similar environments, giving rise to in situ parallel adaptation, is an important hallmark of ecological speciation. However, what appears to be in situ adaptation can also arise by dispersal of divergent lineages from elsewhere. We test whether two contrasting phenotypes repeatedly evolved in parallel, or have a single origin, in an archetypal example of ecological adaptive radiation: benthic-limnetic three-spined stickleback (Gasterosteus aculeatus) across species pair and solitary lakes in British Columbia. We identify two genomic clusters across freshwater populations, which differ in benthic-limnetic divergent phenotypic traits and separate benthic from limnetic individuals in species pair lakes. Phylogenetic reconstruction and niche evolution modeling both suggest a single evolutionary origin for each of these clusters. We detected strong phylogenetic signal in benthic-limnetic divergent traits, suggesting that they are ancestrally retained. Accounting for ancestral state retention, we identify local adaptation of body armor due to the presence of an intraguild predator, the sculpin (Cottus asper), and environmental effects of lake depth and pH on body size. Taken together, our results imply a predominant role for retention of ancestral characteristics in driving trait distribution, with further selection imposed on some traits by environmental factors.

Diet type and prey preference of predators affect intraguild predation between Amblyseius andersoni and Neoseiulus barkeri

Amblyseius andersoni and Neoseiulus barkeri, two species of phytoseiid mites that are widely used for the control of small sucking pests, were found to co-occur on Chinese wolfberry in Inner Mongolia. We investigated the possibility of intraguild predation (IGP) between A. andersoni and N. barkeri to explore the interactions and coexistence of these two species. Predation and oviposition of the two predators on heterospecific juveniles were measured and compared with Tetranychus truncatus or Typha pollen as food, or without alternative food. The mortality rate of N. barkeri juveniles was not affected by the diet treatment, but that of A. andersoni juveniles was reduced by the presence of spider mites. The presence of spider mites also increased oviposition by A. andersoni but not by N. barkeri, and the presence of pollen had no influence on the oviposition of the two predators. Thus, according to the IGP criteria for gaining benefits from predation on heterospecific juveniles, it was concluded that IGP between A. andersoni and N. barkeri occurred, with A. andersoni as intraguild predator and N. barkeri as intraguild prey when spider mites were present. In a further choice test in which heterospecific juveniles and T. truncatus juveniles were provided for each predator, female A. andersoni preferred to prey on N. barkeri rather than on spider mites, whereas female N. barkeri preferred to feed on spider mites rather than on A. andersoni. These findings indicate that the higher preference of N. barkeri on T. truncatus might result in its lower predation on the other predator species compared with A. andersoni and, thus, increased the possibility of the coexistence of the two predator species. Therefore, the occurrence of IGP between A. andersoni and N. barkeri appears to be influenced by the availability and type of the diet and the prey preference of the predators.

Larval feeding types shape the predation aggression of predatory mites in both intraspecific and interspecific encounters

Cannibalism (intraspecific predation) and intraguild (interspecific) predation are widely observed phenomena in the animal kingdom, including amongst predatory mites of the Phytoseiidae family. While the larval stage of phytoseiids is a vulnerable and important life stage, it has received less attention than the adult stage. The larvae of phytoseiid species can be categorised into three types based on their feeding behaviour: non-feeding, facultative feeding, and obligatory feeding. This study aimed to investigate the occurrence of cannibalism and intraguild predation among the larval stages of three generalist predatory phytoseiids: Amblydromalus limonicus (Garman & McGregor), Amblyseius herbicolus (Chant), and Neoseiulus cucumeris (Oudemans). We hypothesised that the larval feeding type could influence the aggressiveness of the predators in intraspecific and interspecific encounters, with obligatory-feeding larvae being the most aggressive and non-feeding larvae being the least aggressive. To test this hypothesis, we conducted a no-choice experiment under laboratory conditions using larvae to observe the prevalence of predation among conspecifics and heterospecifics in these three predatory mite species. In addition to observing predation outcomes, we measured larval body size, cheliceral size, and cheliceral morphology to investigate these parameters’ correlation with predation success. Our study revealed significant differences in the prevalence of cannibalism and intraguild predation among the three predatory species in agreement with our hypothesis: N. cucumeris larvae did not engage in predatory behaviours, while A. herbicolus displayed the highest predation success. Our findings suggest that cheliceral morphology may be a better indicator than body size of the aggressiveness of larval predation against conspecifics and heterospecifics. Our results provide valuable insights into the importance of larval behaviour in population dynamics and the development of effective pest management strategies. The study also highlights the need for further research on the larval stage of phytoseiids and emphasises the significance of considering larval behaviour when studying and managing these important predatory mites.

Scavenger Activity and Anti-Predator Behaviour in an Apennine Wolf Area

Scavenging guilds often have several trophic levels with varying dominance and intra-guild predation, competition, and interaction. Apex predators can control subordinate predators by limiting their numbers and affecting behaviour but also supply a continuous food source by abandoning carcasses. Camera traps monitored the scavenger guild in Alpe di Catenaia, Tuscan Apennine, for three years to determine intraguild interactions and the behaviour response. Wild boar visited most feeding sites but only scavenged in 1.4% of their visits. Red fox was the most frequent scavenger, traded vigilance and feeding equally, and selected low vegetation density, while marten invested more in feeding than vigilance. Marten was the prime follower, appearing within the shortest time after another scavenger had left the site. Red fox occasionally looked upwards, possibly to detect birds of prey. Badger showed scarcely any vigilance, did not feed much on carcasses but scent-marked abundantly. Wolves showed the highest vigilance in proportion to feeding at carcasses among the scavengers. Sites with good visibility were selected by all scavengers except martens who selected poor visibility and new moon illumination. Scavengers were mostly nocturnal, showed weak responses to twilight hours or lunar illumination, and all but red fox avoided human disturbance areas.

Feeding preference and intraguild interactions between the parasitoid Trichogramma achaeae and the predator Macrolophus pygmaeus, two biological agents of Tuta absoluta.

Tuta absoluta is an exotic species and a major pest of tomato crops in Europe. Macrolophus pygmaeus and Trichogramma achaeae are two biocontrol agents widely used in integrated pest management programs of the South American tomato pinworm Tuta absoluta. In this study, we evaluated under laboratory conditions the (i) voracity of M. pygmaeus females fed on single diets of Tuta absoluta eggs parasitized or unparasitized by Trichogramma achaeae, (ii) voracity and feeding preference of M. pygmaeus females provided with mixed diets of Tuta absoluta eggs unparasitized and parasitized by Trichogramma achaeae and (iii) effect of competitive and intraguild interactions between M. pygmaeus and Trichogramma achaeae on the number of Tuta absoluta eggs consumed and/or parasitized. Lastly, we assessed under field conditions the effect of interspecific and intraspecific interactions between natural enemies on the number of Tuta absoluta eggs consumed and/or parasitized. Macrolophus pygmaeus consumed more unparasitized than parasitized eggs of Tuta absoluta. Under mixed diet regimes, Manly indices revealed a feeding preference for unparasitized eggs, and a decrease in the total number of eggs consumed, as the proportion of available parasitized eggs increased, whereas the unparasitized eggs were consumed in direct proportion to their availability. Conspecific interactions between M. pygmaeus, in contrast to Trichogramma achaeae, revealed the possible occurrence of intraspecific competition. For intraguild heterospecific interactions, the number of Tuta absoluta eggs consumed by M. pygmaeus and parasitized by Trichogramma achaeae was lower than that predicted for additive and non-interactive scenarios. Under field conditions, a significant difference between the conspecific treatment and heterospecific treatments revealed a slightly higher success rate in controlling Tuta absoluta when both M. pygmaeus and Trichogramma achaeae were used simultaneously. Macrolophus pygmaeus prefers unparasitized eggs of Tuta absoluta but inflicts intraguild predation on Trichogramma achaeae. In conspecific experiments, mutual interference between M. pygmaeus predators intensifies as the number of individuals increases, but for Trichogramma achaeae, it occurs in an unpredictable manner. Adding Trichogramma achaeae could significantly increase the level of control of Tuta absoluta compared to what could be achieved when only M. pygmaeus is present in glasshouse tomatoes. © 2023 Society of Chemical Industry.

Coexistence of insect species in a phloem feeding guild: Deterministic and stochastic processes

Abstract1. Niche theory, neutral theory, and more recently the unifying theory of biodiversity offer alternative views of the structure (or not) of ecological communities. The relative importance of these theories has not been so thoroughly used to explain community assembly processes in phytophagous insects.2. We studied the mechanisms of community assembly in pine trees phloem feeders, exploring the relative contributions of deterministic and stochastic processes.3. Temporal and spatial partitioning of wood borers and bark beetles belonging to the pine phloem feeding gild, was assessed through flight traps and pine bolts extracted from felled live Pinus pinaster trees presenting evidence of decline/wilting.4. We found that deterministic factors explained most cases of coexistence between species, with partitioning in space and time reducing asymmetric competition for resources and intraguild predation, mediated by differences in size. However, in the case of very closely related species with minimum differences in size—in this case three species of Arhopalus—they occupied the same niche in space and time, suggesting that stochastic processes are more likely to maintain co‐occurrence.5. The present work indicates that both niche and stochastic processes contribute to the assembly of the phloem feeding community. This could be one more example of accordance with the unifying theory of biodiversity.

Intraguild Prey Served as Alternative Prey for Intraguild Predators in a Reciprocal Predator Guild between Neoseiulus barkeri and Scolothrips takahashii

The predatory mites Neoseiulus barkeri (Hughes) and the predatory thrips Scolothrips takahashii (Priesner) are known as potential biocontrol agents for the two-spotted spider mite Tetranychus urticae (Koch). These two predator species occur simultaneously on crops in agricultural ecosystems and are proved to be involved in life-stage specific intraguild predation. The intraguild prey may play a role in securing the persistence of the intraguild predators during food shortage periods. To understand the potential of intraguild prey as food source for intraguild predators in the N. barkeri and S. takahashii guild at low T. urticae densities, the survival, development and reproduction of both predators was determined when fed on heterospecific predators. The choice tests were conducted to determine the preference of the intraguild predator between the intraguild prey and the shared prey. Results showed that 53.3% N. barkeri and 60% S. takahashii juveniles successfully developed when fed on heterospecific predators. Female intraguild predators of both species fed on intraguild prey survived and laid eggs throughout the experiment. In the choice test, both intraguild predator species preferred their extraguild prey T. urticae. This study suggested that intraguild prey served as an alternative prey for intraguild predators prolonged survival and ensured the reproduction of intraguild predators during food shortage, ultimately decreasing the need for the continual release of the predators.

DOES MOONLIGHT SUPPRESS OR STIMULATE ACTIVITY OF A TROPICAL FOREST SMALL MAMMAL

Small nocturnal mammals must balance their activity to maximize foraging efficiency while reducing vulnerability to predators, and moonlight has been widely investigated as a predation risk cue. Didelphis aurita, a nocturnal marsupial, can act as both a competitor and an intraguild predator, and as a prey, increasing or reducing activity under this condition, respectively. We evaluated the effect of moonlight, temperature, and age on the bimodal activity pattern of D. aurita in an Atlantic Forest area, southeastern Brazil. Opossums were more active at low light conditions and in colder nights in the second activity peak. Adults were more active in the second peak, when compared to juveniles and subadults. We suggest that the observed behavior can be a consequence of a preference to periods of low light conditions, to increase foraging efficiency, since D. aurita display features that reflect specialization to scotopic vision such as the tapetum lucidum.

Intraguild Predation by Eurasian Eagle-Owl Bubo bubo on Booted Eagle Aquila pennata and Long-Legged Buzzard Buteo rufinus

In August 2018 remains of several birds of prey were recorded at one Eagle Owl Bubo bubo eyrie in southeast Romania. Among these, still articulated wings and leg bones of an adult female Booted Eagle Aquila pennata, feathers and several bone fragments of one adult Long-legged Buzzard Buteo rufinus and several individuals of Common Buzzards Buteo buteo were identified. While predation of Eagle Owls on different raptor species is well known, booted Eagles and Long-legged Buzzards are rarely preyed upon. Based on changes that occurred in the overall diet of owls at this particular eyrie, it is hypothesized that a shortage in the main prey species (induced by land use changes in the region) may be the cause of these extraordinary predation events. While predation of Eagle Owls on large diurnal raptors is more an exception than a norm, in areas where threatened diurnal raptors breed, the presence of Eagle Owls may cause conservation concerns/prove to be problematic.

Dynamical behaviour of an intraguild predator–prey model with prey refuge and hunting cooperation

ABSTRACT An intraguild predator–prey model including prey refuge and hunting cooperation is investigated in this paper. First, for the corresponding ordinary differential equation model, the existence and stability of all equilibria are given, and the existence of Hopf bifurcation, direction and stability of bifurcating periodic solutions are investigated. Then, for partial differential equation model, the diffusion-driven Turing instability is obtained. What is more, the existence and non-existence of the non-constant positive steady state of the reaction–diffusion model are established by the Leray–Schauder degree theory and some priori estimates. Next, some numerical simulations are performed to support analytical results. The results showed that prey refuge can change the stability of model and even have a stabilizing effect on this model, meanwhile the hunting cooperation can make such model without diffusion unstable, but make such model with diffusion stable. Lastly, a brief conclusion is concluded in the last section.

Modeling and bifurcation analysis of an intraguild predation system

This paper proposes a mathematical model of an asymmetric intraguild (IG) predation system with an exclusive alternative resource. In particular, this paper analyzes the effects that the exclusive alternative resource has on the consumption/predation behaviors of both the IG predator and IG prey species in the system. The results presented on this paper show that, if the IG predator is less competitive in consumption and less efficient in conversion of the shared resource than that of the IG prey, then there exists a lower bound on the value of the predation rate parameter that should be maintained by IG predator species to ensure its survival and co-existence in the system.

Larval and/or Adult Exposure to Intraguild Predator Harmonia axyridis Alters Reproductive Allocation Decisions and Offspring Growth in Menochilus sexmaculatus

Maternal effects can reduce offspring susceptibility to predators by altering resource allocation to young and reproducing larger offspring. While the perception of predation risk can vary according to a prey’s life stage, it is unclear whether maternally experienced intraguild predation (IGP) risk during different life stages influences the maternal effects of predatory insects. We investigated the influence of exposure to intraguild predators (Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae)) during the larval and/or adult stages on reproductive decisions and offspring growth in Menochilus sexmaculatus (Fabricius). Independent of the life stage, when M. sexmaculatus females experienced IGP risk, their body weight and fecundity decreased, but the proportion of trophic eggs produced increased. However, egg mass, egg clutch number, and egg clutch size were not influenced by the treatment. Next, when offspring encountered H. axyridis, mothers experiencing IGP risk during the larval and/or adult stages could increase their offspring’s weight. Moreover, offspring in IGP environments reached a similar size as those with no-IGP environments when mothers experienced IGP risk during the larval and/or adult stages. Overall, M. sexmaculatus larval and/or adult exposure to IGP risk had no influence on egg size, but increased offspring body size when faced with H. axyridis. Additionally, mothers experiencing IGP risk during different life stages showed increased production of trophic eggs. Because IGP is frequently observed on M. sexmaculatus and favours relatively larger individuals, different stages of M. sexmaculatus express threat-sensitively to IGP risk; inducing maternal effects can be an adaptive survival strategy to defend against H. axyridis.

The Fall Armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae), Influences Nilaparvata lugens Population Growth Directly, by Preying on Its Eggs, and Indirectly, by Inducing Defenses in Rice.

The fall armyworm (FAW), Spodoptera frugiperda, has become one of the most important pests on corn in China since it invaded in 2019. Although FAW has not been reported to cause widespread damage to rice plants in China, it has been sporadically found feeding in the field. If FAW infests rice in China, the fitness of other insect pests on rice may be influenced. However, how FAW and other insect pests on rice interact remains unknown. In this study, we found that the infestation of FAW larvae on rice plants prolonged the developmental duration of the brown planthopper (BPH, Nilaparvata lugens (Stål)) eggs and plants damaged by gravid BPH females did not induce defenses that influenced the growth of FAW larvae. Moreover, co-infestation by FAW larvae on rice plants did not influence the attractiveness of volatiles emitted from BPH-infested plants to Anagrus nilaparvatae, an egg parasitoid of rice planthoppers. FAW larvae were able to prey on BPH eggs laid on rice plants and grew faster compared to those larvae that lacked available eggs. Studies revealed that the delay in the development of BPH eggs on FAW-infested plants was probably related to the increase in levels of jasmonoyl-isoleucine, abscisic acid and the defensive compounds in the rice leaf sheaths on which BPH eggs were laid. These findings indicate that, if FAW invades rice plants in China, the population density of BPH may be decreased by intraguild predation and induced plant defenses, whereas the population density of FAW may be increased.

Dipteran Prey Vulnerability in Intraguild Predation (IGP) System Involving Heteropteran Predators: Density and Habitat Effects

(1) Background: The effects of density and the habitat conditions on the prey vulnerability in the Intraguild Predation (IGP) system were evaluated using the water bug D. rusticus as the top predator. (2) Methods: Using two different density levels (low or high) of the dipteran prey (mosquito and chironomid), the IGP system was set with A. bouvieri as the IG prey. (3) Results: The prey vulnerability was reduced in complex habitat conditions, irrespective of the prey and predator density levels and the prey identity. Correspondingly, the IG prey vulnerability was higher in the low shared prey density and complex habitat. The IG prey consumption by the top predator was higher with the mosquito as shared prey than chironomid as shared prey. Observations on the prey consumption indicated that the consumption of both the chironomid and the mosquito prey dwindled with the time for all combinations of the prey density and the habitat conditions. On a comparative scale, the prey clearance rates were higher for mosquitoes in contrast to the chironomid larvae as shared prey. (4) Conclusions: Apparently, a complex set of interactions involving the habitat conditions, top predator and the prey determines mosquito prey vulnerability against the water bug. Such interactions provide evidence for the coexistence of the mosquito larvae along with multiple predators in the wetland ecosystem.

Concurrent dilution and amplification effects in an intraguild predation eco-epidemiological model

The dilution and amplification effects are important concepts in the field of zoonotic diseases. While the dilution effect predicts that pathogen prevalence is negatively correlated with increased species diversity, the opposite trend is observed when the amplification effect occurs. Understanding how interspecific interactions such as predation and competition within a community influence disease transmission is highly relevant. We explore the conditions under which the dilution and amplification effects arise, using compartmental models that integrate ecological and epidemiological interactions. We formulate an intraguild predation model where each species is divided into two compartments: susceptible and infected individuals. We obtained that increasing predation increases the disease transmission potential of the predator and the density of infected individuals, but decreases the disease transmission potential of the prey, as well as their density. Also, we found that interspecific competition always helps to decrease the number of infected individuals in the population of the two species. Therefore, dilution and amplification effects can be observed simultaneously but depending on different types of cological interactions.

A tiny cuckoo: Risk‐dependent interspecific brood parasitism in a predatory mite

Abstract Many animal species protect their eggs against predators, and other species may profit from this by adding their eggs to those of the protecting species. We studied two tiny species of predatory mites that share a food source, are engaged in intraguild predation, and which eggs are attacked by the same egg predator. One of these predatory mites (Neoseiulus californicus) adds its eggs to those of the other species (Gynaeseius liturivorus) which guards its eggs from egg predators, resulting in reduced predation of the eggs of the nonguarding species. The guarding species experiences costs in the form of intraguild predation of her offspring, and the addition of eggs to the guarding species therefore qualifies as brood parasitism. In the presence of egg predators, the brood parasite preferentially adds its eggs to those of the guarding host species, not to those of another, nonguarding mite species. This cuckoo behaviour comes with a cost for the parasite when egg predators are absent, and therefore only occurs when egg predators are present. Our findings emphasize the importance of the risk of egg predation as a factor driving facultative brood parasitism. Read the free Plain Language Summary for this article on the Journal blog.

The Effects of Intraguild Predation on Phytoplankton Assemblage Composition and Diversity: A Mesocosm Experiment.

Intraguild predation (IGP) can have a significant impact on phytoplankton biomass, but its effects on their diversity and assemblage composition are not well understood. In this study, we constructed an IGP model based on the common three-trophic food chain of "fish (or shrimp)-large branchiopods (Daphnia)-phytoplankton", and investigated the effects of IGP on phytoplankton assemblage composition and diversity in outdoor mesocosms using environmental DNA high-throughput sequencing. Our results indicated that the alpha diversities (number of amplicon sequence variants and Faith's phylogenetic diversity) of phytoplankton and the relative abundance of Chlorophyceae increased with the addition of Pelteobagrus fulvidraco, while similar trends were found in alpha diversities but with a decrease in the relative abundance of Chlorophyceae in the Exopalaemon modestus treatment. When both predators were added to the community, the strength of collective cascading effects on phytoplankton alpha diversities and assemblage composition were weaker than the sum of the individual predator effects. Network analysis further showed that this IGP effect also decreased the strength of collective cascading effects in reducing the complexity and stability of the phytoplankton assemblages. These findings contribute to a better understanding of the mechanisms underlying the impacts of IGP on lake biodiversity, and provide further knowledge relevant to lake management and conservation.

Hot or hungry? A tipping point in the effect of prey depletion on African wild dogs

Interspecific competition has strong effects within carnivore guilds, and African wild dogs are strongly limited by intraguild predation by lions and food loss to spotted hyenas. The densities of these dominant competitors correlate tightly with prey density, and prey depletion due to snaring is contributing to declines of apex carnivores across Africa. As a consequence of snaring, subordinate competitors like the African wild dog and cheetah are simultaneously experiencing a costly reduction in prey and a beneficial reduction of competitors. The net effect is difficult to predict. Here, we describe a previously unrecognized tipping point in the effect of prey density on wild dog density. Above this tipping point, wild dog density increases as prey density decreases, because the benefits of competitive release outweigh the costs of prey depletion. Below this tipping point, wild dog density decreases as prey density decreases, because the costs of prey depletion outweigh the benefits of competitive release. Conservation strategies for wild dogs must recognize this tipping point. As prey depletion due to snaring becomes severe, it limits wild dogs (mesocarnivores), just as it does lions and spotted hyenas (apex carnivores). Recent analyses based on time trends have argued that climate change is likely to cause wild dog populations to collapse. We suggest that prey depletion provides a mechanistically direct explanation of patterns in wild dog dynamics that have been attributed to climate change, and that the effects of prey depletion are likely to go unrecognized in the absence of data on trends in prey density.

Intraguild predation as a potential explanation for the population decline of the threatened native fish, the European mudminnow (Umbra krameri Walbaum, 1792) by the invasive Amur sleeper (Perccottus glenii Dybowski, 1877)

Biotic interactions exerted by invasive species have a strong effect on ecosystems. Intraguild predation may contribute to the decline in the distribution, abundance and population size of native species and may facilitate the spread of non-native taxa. In this study, we investigated the feeding ecology of the invasive fish Amur sleeper (Perccottus glenii Dybowski, 1877) in a lowland watercourse, where it co-exists with the threatened native fish European mudminnow (Umbra krameri Walbaum, 1792). We used two sampling protocols that differed in the frequency of sampling time (e.g. monthly samplings and samplings in 10-day intervals) to provide evidence of predation, an interaction that may lead to the decline of mudminnow populations with the spread of the Amur sleeper. Aquatic macroinvertebrates comprised a major part of the diet for both sampling intervals. However, finer temporal resolution revealed the importance of fish, especially mudminnow juveniles, as a periodically available food source in the Amur sleeper’s diet. A high degree of dietary overlap was found between the different size groups of the Amur sleeper, but larger specimens tended to feed on a relatively higher proportion of fish. Our results suggested that temporal resolution of stomach content analyses may largely determine inferences on the importance of predation on juvenile mudminnow. Overall, we found that intraguild predation could contribute to the decline of European mudminnow populations, which underscores the importance of effective control measures to prevent the further spread of the invasive Amur sleeper.