Multispecies Associations Research Articles

Bryde’s whale (Balaenoptera edeni) occurrence and foraging behaviour along the east coast of Australia

ABSTRACT Despite their global occurrence in warm-temperate waters and their suspected non-migratory lifestyle, Bryde’s whales (Balaenoptera edeni spp.) are considered the least-known large baleen whale species. In Australian waters, information on their distribution, ecology and behaviour is scarce. This study documents Bryde’s whale occurrence and foraging behaviours along the Australian East Coast using opportunistic citizen science sightings via drone aerial photography, vessel and land-based observations. We observed foraging in both shallow (seafloor visible, beach and breaking waves present) and deep waters. We observed a range of foraging behaviours including lunge feeding (exhibited by individual whales and in pairs), sub-surface and surface skim feeding (shallow waters only) and described multispecies associations. We describe a potentially novel feeding behaviour in shallow waters, where Bryde’s whales are feeding directly within or behind the surf break (shallow water surf feeding). We quantify the presence of mother-calf pairs in Australian waters, highlighting the use of these waters for potential calving. This study provides insights into Bryde’s whale occurrence and foraging behaviour in both shallow and deep waters of eastern Australia.

A fish can change its stripes: investigating the role of body colour and pattern in the bluelined goatfish.

Bluelined goatfish (Upeneichthys lineatus) rapidly change their body colour from a white horizontally banded pattern to a seemingly more conspicuous vertically banded red pattern, often when foraging. Given the apparent conspicuousness of the pattern to a range of observers, it seems unlikely that this colour change is used for camouflage and instead may be used for communication/signalling. Goatfish often drive multispecies associations, and it is possible that goatfish use this colour change as a foraging success signal to facilitate cooperation, increase food acquisition, and reduce predation risk through a 'safety in numbers' strategy. Using a novel approach, we deployed 3D model goatfish in different colour morphs-white without bands, white with black vertical bands, and white with red vertical bands-to determine whether the red colouration is an important component of the signal or if it is only the vertical banding pattern, regardless of colour, that fish respond to as an indicator of foraging success. Use of remote underwater video allowed us to obtain information without the influence of human observers on the communities and behaviours of other fish in response to these different colours exhibited by goatfish. We found that conspecifics were more abundant around the black- and red-banded model fish when compared with the white models. Conspecifics were also more likely to forage around the models than to pass or show attraction, but this was unaffected by model colour. No difference in the abundance and behaviour of associated heterospecifics around the different models was observed, perhaps due to the static nature of the models. Some species did, however, spend more time around the red- and black-banded fish, which suggests the change in colour may indicate benefits in addition to food resources. Overall, the results suggest that the body colour/pattern of U. lineatus is likely a signalling tool but further work is required to explore the benefits to both conspecifics and heterospecifics and to further determine the behavioural functions of rapid colour change in U. lineatus.

Dynamics of tall fescue (Festuca arundinacea) and Kikuyu grass (Cenchrus clandestinus) pastures associated with white clover (Trifolium repens) in small-scale dairy systems in the highlands of central Mexico

An on-farm participatory study was undertaken to assess changes over seasons on the availability, botanical and morphological composition, and nutritive value of herbage from two pastures in small-scale dairy systems in the highlands of central Mexico. One pasture (TF-33) was originally sown with tall fescue, while the second pasture (KY) was naturally invaded by Kikuyu grass; both associated with white clover and over-sown in winter with annual ryegrass. Sampling was every 28 days for a year. Variables were sward height, net herbage accumulation, soil cover, tiller density, chemical composition, and in vitro digestibility. A split-plot design was used. Sward height was greater for KY. There were no differences (p > 0.05) for herbage accumulation. TF-33 was 53% live tissue, 30% dead tissue, and 17% other plant material, whilst KY was 50% live tissue, 30% dead tissue, and 18% other plant material. TF-33 showed a higher leaf to stem proportion, while stem was higher in KY. Kikuyu grass and annual ryegrass performed better when associated with TF-33 than in KY pasture. Seasonal changes significantly affected sward height, herbage mass and net herbage accumulation, whereby TF-33 performed better than KY in winter. The multispecies association of diverse grasses and legumes may be complementary at different times of the year due to plasticity among species, and is a feasible option for small-scale dairy systems.

The potential of introducing new variety of Acacia hybrids in agroforestry systems

The increases of multiple economic uses and ecological functions are among the essential targets in developing agroforestry systems. In this case, selecting the appropriate species with the range of characters adapted to agroforestry systems would become important. Breeding practices could be applied to produce high productive trees with such desired characters. Some Acacias species have been commonly planted under agroforestry systems in several locations, particularly in Java Island, due to producing good quality of wood for home industries and the ability to grow in multi-species associations. Acacia hybrids are new variety resulted from breeding through a crossing between two Acacias: Acacia mangium and A. auriculiformis. The main target of breeding for this variety is to produce a higher quality of wood combining the good properties from each both of parents in a shorter rotation. Although the breeding process mainly imposed the selection for better growth, tolerance pest and disease, and wood properties as primary economic production, the variety also performs other potential characters suitable for agroforestry systems such as light branching for stimulating the growth of crops, abundant flowers for increasing food for honey bee, produce tannin from bark residu, and high quality of wood pellet from the sawdust.

Predicting ecosystem responses to changes in fisheries catch, temperature, and primary productivity with a dynamic Bayesian network model

Abstract The recent adoption of Bayesian networks (BNs) in ecology provides an opportunity to make advances because complex interactions can be recovered from field data and then used to predict the environmental response to changes in climate and biodiversity. In this study, we use a dynamic BN model with a hidden variable and spatial autocorrelation to explore the future of different fish and zooplankton species, given alternate scenarios, and across spatial scales within the North Sea. For most fish species, we were able to predict a trend of increase or decline in response to change in fisheries catch; however, this varied across the different areas, outlining the importance of trophic interactions and the spatial relationship between neighbouring areas. We were able to predict trends in zooplankton biomass in response to temperature change, with the spatial patterns of these effects varying by species. In contrast, there was high variability in terms of response to productivity changes and consequently knock-on effects on higher level trophic species. Finally, we were able to provide a new data-driven modelling approach that accounts for multispecies associations and interactions and their changes over space and time, which might be beneficial to give strategic advice on potential response of the system to pressure.

Reconciling catch differences from multiple fishery independent gill net surveys

Fishery independent gill net surveys provide valuable demographic information for population assessment and resource management, but relative to net construction, the effects of ancillary species, and environmental variables on focal species catch rates are poorly understood. In response, we conducted comparative deployments with three unique, inter-agency, survey gill nets used to assess walleye Sander vitreus in Lake Erie. We used an information-theoretic approach with Akaike’s second-order information criterion (AICc) to evaluate linear mixed models of walleye catch as a function of net type (multifilament and two types of monofilament netting), mesh size (categorical), Secchi depth, temperature, water depth, catch of ancillary species, and interactions among selected variables. The model with the greatest weight of evidence showed that walleye catches were positively associated with potential prey and intra-guild predators and negatively associated with water depth and temperature. In addition, the multifilament net had higher average walleye catches than either of the two monofilament nets. Results from this study both help inform decisions about proposed gear changes to stock assessment surveys in Lake Erie, and advance our understanding of how multispecies associations explain variation in gill net catches. Of broader interest to fishery-independent gill net studies, effects of abiotic variables and ancillary species on focal specie’s catch rates were small in comparison with net characteristics of mesh size or twine type.

The multispecies formicary association: the transition from an incomplete to a complete association

This work describes the transformation of the nest complex of a facultatively dominant species, Formica cunicularia, which was naturally colonized by the families of obligate dominants, Formica pratensis and Lasius fuliginosus. The complex was under observation from 2003 to 2013. During this period, F. pratensis families almost completely replaced F. cunicularia in the tenth part of the territory of this multispecies association. The family L. fuliginosus did not exert such an effect on the settlement of the facultative dominant. The study addresses the interaction of foragers of the species that found themselves in the zone of F. pratensis invasion, the dynamics of expansion of the dominant’s foraging areas, and the changes in the multispecies formicary association on the whole. It is shown that, even with different peaceful coexistence mechanisms at work, the alteration of the association occurs through attacks of the obligate dominant on the neighboring families. The progress of this process and possible key situations are considered.

Co-Occurrence and Habitat Use of Fin Whales, Striped Dolphins and Atlantic Bluefin Tuna in the Northwestern Mediterranean Sea.

Different dolphin and tuna species have frequently been reported to aggregate in areas of high frontal activity, sometimes developing close multi-species associations to increase feeding success. Aerial surveys are a common tool to monitor the density and abundance of marine mammals, and have recently become a focus in the search for methods to provide fisheries-independent abundance indicators for tuna stock assessment. In this study, we present first density estimates corrected for availability bias of fin whales (Balaenoptera physalus) and striped dolphins (Stenella coeruleoalba) from the Golf of Lions (GoL), compared with uncorrected estimates of Atlantic bluefin tuna (ABFT; Thunnus thynnus) densities from 8 years of line transect aerial surveys. The raw sighting data were further used to analyze patterns of spatial co-occurrence and density of these three top marine predators in this important feeding ground in the Northwestern Mediterranean Sea. These patterns were investigated regarding known species-specific feeding preferences and environmental characteristics (i. e. mesoscale activity) of the survey zone. ABFT was by far the most abundant species during the surveys in terms of schools and individuals, followed by striped dolphins and fin whales. However, when accounted for availability bias, schools of dolphins and fin whales were of equal density. Direct interactions of the species appeared to be the exception, but results indicate that densities, presence and core sighting locations of striped dolphins and ABFT were correlated. Core sighting areas of these species were located close to an area of high mesoscale activity (oceanic fronts and eddies). Fin whales did not show such a correlation. The results further highlight the feasibility to coordinate research efforts to explore the behaviour and abundance of the investigated species, as demanded by the Marine Strategy Framework Directive (MSFD).

Mutualistic relationships between the shield ant, Meranoplus bicolor (Guérin–Méneville) (Hymenoptera: Formicidae) and honeydew–producing hemipterans in guava plantation

ABSTRACT – Mutualistic relationship between the shield ant, Meranoplus bicolor (Guerin–Meneville), and two species of hemipteran, Aphis gossypii Glover and Ferrisia virgata (Cockerell), was investigated in an unsprayed guava plot at Kamphaeng Saen, Nakhon Pathom, Thailand. The reciprocal benefits were observed in both field and laboratory studies. M. bicolor activity coincided with peak seasonal activity of both hemipterans during June–August. We indicate two sets of support evidence in M. bicolor honeydew preference: (i) statistically higher value of adjusted honeydew weight collected by ant worker from A. gossypii compared with that from F. virgata ( p –value = .005), and (ii) the higher value of the strength of effect (h 2 = .62) in the total variance of multi-species association. We used two–group, ant–tended and ant–excluded, between–subject multivariate analysis of variance (MANOVA) in order to show hemipteran benefits. Both hemipteran populations increased in the ant–tended treatment, together with lesser amounts of two species of coccinellids, Menochilus sexmaculatus (Fabricius) and Coccinella transversalis Fabricius, and one species of syrphid fly, Pseudodorus clavatus (Fabricius), compared with the ant exclusion treatment ( p –value <.0005). The facultative mutualistic relationships of M. bicolor and the two hemipteran species were evaluated.

Survey of the mosquitoes (Diptera: Culicidae) of Mayotte.

A transversal survey of immature mosquitoes was conducted on Mayotte Island (France) in the Comoros Archipelago, western Indian Ocean, with the aim to inventory the Culicidae and to document inter-species relationships in different habitats. In total 420 habitats were sampled for larvae and/or pupae mosquitoes, resulting in more than 6,000 specimens. Forty species belonging to 15 genera were collected, with eight taxa integrated for the first time to the Mayotte mosquito list. The most frequently recorded species were Stegomyia aegypti, St. albopicta, Anopheles gambiae and Eretmapodites subsimplicipes, the first three species being known vectors of viruses and parasites transmitted to humans. Mean species richness in habitats ranged from 1.00 to 3.29, with notable differences between habitats. For example, water-filled axils of banana leaves, tree-holes and crab-holes had low species richness, while cut bamboo, water pools, abandoned tires and marsh and swamp water had notably higher species richness. Twenty-seven mosquito species belonging to 12 genera were routinely collected (in ≥20% of at least one type of larval habitat) suggesting that multiple species play a role in the biocenosis of these aquatic habitats. Multispecies association was observed in 52% of the habitats. The co-occurrence of up to six species belonging to five genera was recorded in a single habitat. The mosquitoes of Mayotte show notable biogeographical affinities to those of Madagascar, as compared to the African continent. These two potential source areas are nearly equidistant from Mayotte, which in turn indicates biased dispersal from east to west. Our findings suggest that with relatively short-term intensive sampling in different habitats, it is possible to approach exhaustive species inventories based on collection of larvae. Mayotte, with its modest elevation range and land surface, has a notable species richness of mosquitoes with 45 well-documented species belonging to 15 genera.

Deception by Flexible Alarm Mimicry in an African Bird

Deception is common in nature, but victims of deception discriminate against and ultimately ignore deceptive signals when they are produced too frequently. Flexible variation of signals could allow evasion of such constraints. Fork-tailed drongos (Dicrurus adsimilis) use false alarm calls to scare other species away from food that they then steal. We show that drongos mimic the alarms of targeted species. Further, target species reduce their response to false alarm calls when they are repeated. However, the fear response is maintained when the call is varied. Drongos exploit this propensity by changing their alarm-call type when making repeated theft attempts on a particular species. Our results show that drongos can evade the frequency-dependent constraints that typically limit deception payoffs through flexible variation of their alarm calls.

To Eat and Not Be Eaten: Modelling Resources and Safety in Multi-Species Animal Groups

Using mixed-species bird flocks as an example, we model the payoffs for two types of species from participating in multi-species animal groups. Salliers feed on mobile prey, are good sentinels and do not affect prey capture rates of gleaners; gleaners feed on prey on substrates and can enhance the prey capture rate of salliers by flushing prey, but are poor sentinels. These functional types are known from various animal taxa that form multi-species associations. We model costs and benefits of joining groups for a wide range of group compositions under varying abundances of two types of prey–prey on substrates and mobile prey. Our model predicts that gleaners and salliers show a conflict of interest in multi-species groups, because gleaners benefit from increasing numbers of salliers in the group, whereas salliers benefit from increasing gleaner numbers. The model also predicts that the limits to size and variability in composition of multi-species groups are driven by the relative abundance of different types of prey, independent of predation pressure. Our model emphasises resources as a primary driver of temporal and spatial group dynamics, rather than reproductive activity or predation per se, which have hitherto been thought to explain patterns of multi-species group formation and cohesion. The qualitative predictions of the model are supported by empirical patterns from both terrestrial and marine multi-species groups, suggesting that similar mechanisms might underlie group dynamics in a range of taxa. The model also makes novel predictions about group dynamics that can be tested using variation across space and time.

Seasonal fluctuations in occurrence of inshore Bryde's whales in Plettenberg Bay, South Africa, with notes on feeding and multispecies associations

Seasonal fluctuations in the occurrence of inshore South African Bryde's whales Balaenoptera edeni were investigated between November 2005 and June 2008. Sighting data were collected in Plettenberg Bay on the south-east coast of South Africa. Bryde's whale occurrence was modelled in relation to the following environmental covariates: sea surface temperature, chlorophyll a concentrations and wind speed. Seasonal increases in encounter rates (sightings per day) were observed during summer and autumn, with a peak in April that corresponded to increased feeding activity and above average aggregation sizes. All three environmental covariates were significant factors in terms of explaining variability in the occurrence of whales. Multispecies associations with common dolphins Delphinus capensis and Cape gannets Morus capensis were most common in summer and autumn, when feeding activity was highest.

An analysis of mutualistic interactions between exotic ants and honeydew producers in the Yanbaru district of Okinawa Island, Japan

AbstractInvasive exotic ants often have a mutualistic relationship with other insects excreting honeydew, and this is considered to play a key role in their invasion success. We investigated the multispecies association patterns between ants and hemipteran insects in the Yanbaru forests, Okinawa, Japan, an Asian biodiversity hotspot. We especially focused on roadside environments, which are the frontlines of invasion for exotic ants. We found that only a small number of herbaceous and pioneer plants were predominant on the roadsides. Four honeydew producers, Melanaphis formosana, Dysmicoccus sp. A, Heteropsylla cubana, and Sogata hakonensis, living on these roadside plants accounted for 94.9% of the total honeydew‐producer aggregations observed. Only a few exotic ants, such as Technomyrmex brunneus and Anoplolepis gracilipes, were observed with these honeydew‐producer aggregations, and densities of these ants and honeydew producers were often positively correlated. An ant exclusion experiment showed that exotic ant occurrence improved the survival of some of the hemipteran colonies. Interestingly, the abundance of native ants was not correlated with the abundance of honeydew producers, and the local density of Pheidole noda was negatively correlated with that of M. formosana. These findings, i.e., only a few ants, all exotic, tended to hemipteran honeydew producers despite the existence of many native ants, and the abundances of those exotic ants and those hemipteran insects had positive correlations, provide some insights into the mechanism of biological invasion and provide information for the management of exotic ants.

Evolution in metacommunities

A metacommunity can be defined as a set of communities that are linked by migration, and extinction and recolonization. In metacommunities, evolution can occur not only by processes that occur within communities such as drift and individual selection, but also by among-community processes, such as divergent selection owing to random differences among communities in species composition, and group and community-level selection. The effect of these among-community-level processes depends on the pattern of migration among communities. Migrating units may be individuals (migrant pool model), groups of individuals (single-species propagule pool model) or multi-species associations (multi-species propagule pool model). The most interesting case is the multi-species propagule pool model. Although this pattern of migration may a priori seem rare, it becomes more plausible in small well-defined 'communities' such as symbiotic associations between two or a few species. Theoretical models and experimental studies show that community selection is potentially an effective evolutionary force. Such evolution can occur either through genetic changes within species or through changes in the species composition of the communities. Although laboratory studies show that community selection can be important, little is known about how important it is in natural populations.

The behavior of ants of different species during joint foraging

The interaction between ants with different levels of social and territorial organization (Formica polyctena, Myrmica rubra, M. ruginodis, M. schencki, Lasius niger, and Formica fusca) was studied in the Ugra National Park (Kaluga Prov., Russia). The behavior of ants competing for an abundant source of food (carbohydrate feeders) was analyzed. It was found that the possibility of ants coexisting in a multi-species association was ensured, in particular, by different strategies of feeding behavior. A species with effective mobilization may achieve a greater competitive success as compared to more aggressive but less effectively mobilizing ones. Species characterized by non-aggressive behavior and ineffective mobilization may ensure their biological success due to an efficient system of foraging.

Neighborhood phylodiversity affects plant performance

Facilitation and competition are ecological interactions that are crucial for the organization of plant communities. Facilitative interactions tend to occur among distantly related species, while the strength of competition tends to decrease with phylogenetic distance. The balance between both types of interactions will ultimately determine the specific composition of multispecies associations. Although multispecies patches are the arena in which coexistence develops among different phylogenetic groups within communities, the specific processes that occur across life stages have not been explored. Here we study how different species, in composing discrete patches in central Mexico, exert competitive or facilitative effects on seeds and seedlings. We relate these interactions to phylogenetic relationships among nurse species and beneficiary species, and among members of the patches. Survivorship and growth rates of the columnar cactus Neobuxbaumia mezcalaensis were highly positively related to increasing phylogenetic distance to different nurse species, to the presence of related species in patches, and to mean phylogenetic distances to the rest of the species in the patch. Each of these three elements influenced N. mezcalaensis differently, with different nurse species varying substantially in their early effects on emergence, and the nearest relatives and species composition of patches varying in their late effects on survival and growth. Our results emphasize that evolutionary relationships among co-occurring species in vegetation clumps exert direct and indirect effects on plants, affecting individual performance and species coexistence.

The nuclear question: rethinking species importance in multi‐species animal groups

1. Animals group for various benefits, and may form either simple single-species groups, or more complex multi-species associations. Multi-species groups are thought to provide anti-predator and foraging benefits to participant individuals. 2. Despite detailed studies on multi-species animal groups, the importance of species in group initiation and maintenance is still rated qualitatively as 'nuclear' (maintaining groups) or 'attendant' (species following nuclear species) based on species-specific traits. This overly simplifies and limits understanding of inherently complex associations, and is biologically unrealistic, because species roles in multi-species groups are: (i) likely to be context-specific and not simply a fixed species property, and (ii) much more variable than this dichotomy indicates. 3. We propose a new view of species importance (measured as number of inter-species associations), along a continuum from 'most nuclear' to 'least nuclear'. Using mixed-species bird flocks from a tropical rainforest in India as an example, we derive inter-species association measures from randomizations on bird species abundance data (which takes into account species 'availability') and data on 86 mixed-species flocks from two different flock types. Our results show that the number and average strength of inter-species associations covary positively, and we argue that species with many, strong associations are the most nuclear. 4. From our data, group size and foraging method are ecological and behavioural traits of species that best explain nuclearity in mixed-species bird flocks. Parallels have been observed in multi-species fish shoals, in which group size and foraging method, as well as diet, have been shown to correlate with nuclearity. Further, the context in which multi-species groups occur, in conjunction with species-specific traits, influences the role played by a species in a multi-species group, and this highlights the importance of extrinsic factors in shaping species importance. 5. Our view of nuclearity provides predictive power in examining species roles in a variety of situations (e.g. predicting leadership in differently composed communities), and can be applied to examine a broad range of ecological and evolutionary questions pertinent to multi-species groups in general.

The Gyrinidae (Coleoptera) of the Maritime Provinces of Canada: new records, distribution, and faunal composition

The Gyrinidae (whirligig beetles) of the Maritime Provinces of Canada are surveyed. Twenty-two species are now known to occur in the region, 19 of which have been recorded from Nova Scotia, 17 from New Brunswick, and 9 from Prince Edward Island. Seven species are newly recorded in Nova Scotia, and four in New Brunswick. Two of these, Gyrinus dichrous LeConte and Gyrinus gehringi Chamberlain, are newly recorded in the Maritime Provinces. The zoogeographic composition of the fauna within the region is briefly examined, the species falling into six categories. Islands portions of Atlantic Canada (Prince Edward Island, Cape Breton, and insular Newfoundland) have a diminished fauna, roughly 40% that of neighbouring mainland areas. The proportionate composition of the gyrinid fauna in various portions of Atlantic Canada is similar to that of the Carabidae (a much larger suite of beetles that have been more extensively investigated) with the exception of New Brunswick, where a diminished number of recorded gyrinids would appear to indicate an insufficient collecting effort for this family in the province. Finally, a preliminary examination of multispecies associations is presented which indicates that some species more frequently engage in such aggregations than others.

Temperature selection by tropical bats roosting in caves

The temperature preferences of the mormoopid and phyllostomid bats Pteronotus quadridens and Erophylla sezekorni, from the West Indies, were determined in the laboratory and compared to field observations. Pteronotus quadridens was invariably found within the deepest and hottest parts of caves, at temperatures between 28°C and 35°C, while E. sezekorni was found at temperatures from 25°C to 28°C. Temperatures selected by each species in a thermopreferendum chamber were similar to their respective roosting temperatures in the caves. These inter-specific differences are statistically significant. Our results support the hypothesis that roost temperature and differences in temperature preferences among species, are important in explaining multispecies associations and the spatial segregation within caves.