In fish, social interactions are commonly accompanied by acoustic signalling. Males have been found to produce sounds in a large range of species, but female sounds have received considerably less ...attention. But even in males, there remain significant taxonomical gaps, e.g. in one of the largest fish families, the wrasses. Here, we investigate sound production in territorial males and females of the corkwing wrasse in a field study in Norway. We complemented an in-depth analysis of the visual and acoustic behavioural repertoire of territorial males by descriptions of female behaviours. Males as well as females produced sounds in courtship and agonistic contexts. We recorded four types of sounds and found significant differences between male and female sound properties. We hereby provide one of the first descriptions of sound production in wrasses and, to our knowledge, the first one to also investigate female sound production. Our study shows that wrasses are an underappreciated family when it comes to sound production. With a repertoire of four different calls, corkwing wrasses are remarkably versatile among fishes. Our results highlight the potential and importance of future research about sound communication in neglected taxa, and in both sexes.
The present study investigated whether temperate wrasses in a geographical location in the southern hemisphere break open crab prey on anvils. Here, tool‐use behaviour is reported in two temperate ...wrasses, the orange wrasse Pseudolabrus luculentus and the doubleheader Coris bulbifrons, at Lord Howe Island, Australia. In addition to the previous observations of this behaviour, these findings suggest that tool use is common and may be ubiquitous, in medium‐sized carnivorous wrasses that are undergoing an ontogenetic shift from soft‐bodied to hard‐shelled prey.
The movement patterns of three commercially important wrasse (Labridae) species inside a small marine protected area (~ 0.15 km2) on the west coast of Norway were analysed over a period of 21 months. ...The mean distance between capture and recapture locations varied between 10 and 187 m, and was species and season specific. The extent of movement was not related to body size or sex. These results imply that a network of small strategically located marine protected areas can be used as management tools to protect wrasses from size‐ and sex‐selective fishing mortality.
Mutualisms are pivotal in shaping ecological communities. Iconic images of cleaner fish entering the mouths of predatory fish clients to remove ectoparasites epitomize their mutual benefit. ...Experimental manipulations of cleaner wrasse reveal declines in fish size and growth, and population abundance and diversity of client fishes in the absence of cleaner wrasse. Fishes grow more slowly and are less abundant and diverse on reefs without cleaner wrasse, both for larger species that are regularly cleaned and have high ectoparasite loads (“attractive species”), and for those smaller species that are rarely cleaned and are rarely infested with parasites (“unattractive species”). We therefore considered whether these previously observed declines in individual and population parameters on reefs without cleaners were related to increased ectoparasite infestation using an attractive species (
Hemigymnus melapterus
, Labridae) and an unattractive species (
Pomacentrus amboinensis
, Pomacentridae). Traps with these fish as a form of bait were deployed to sample blood-sucking gnathiid ectoparasites (Gnathiidae: Isopoda) on reefs from which cleaners (
Labroides dimidiatus
, Labridae) have been removed for 13 yr. Cleaner fish could not enter traps to access the clients/hosts, but gnathiids could enter the traps to infest hosts; thus, this method sampled the indirect effect of cleaners on gnathiid infestation of fish. Infestation was higher on reefs without cleaners than on those with them. The effect was only detected during the daytime when cleaners are active and only on the attractive species (
H. melapterus
). Thus, cleaner presence indirectly reduced fish exposure to parasites in a species that is highly susceptible to parasites, but not in one that is rarely infested with parasites. This suggests that cleaner presence indirectly reduces exposure of a common fish species to harmful parasites, which may explain some observed benefits in fishes at this location.
In the present study, Xyrichtys novacula (Labridae) were sampled at five locations around the islands of Ibiza and Formentera (western Mediterranean Sea). Isotopic signatures of d13C, d15N and the ...C:N ratio were analysed in relation to locality, sex and size differences. d13C and d15N partitioning was also studied in the reproductive spawning period. There were significant differences in the d13C signature between localities for both sexes, but not for d15N. Sex differences were also found with a mean cs.e. value of -17.38 c 0.06ppt d13C and 8.36 c 0.05ppt d15N for females and -17.17 c 0.07ppt d13C and 8.80 c 0.06ppt d15N for males. Increasing total length in both sexes was positively correlated with d15N enrichment and a significant positive linear regression was established for both variables. During the reproductive spawning period, there were changes in d13C fractioning with enrichment in postspawning females and males (with respect to prespawning and spawning periods) and d15N impoverishment in postspawning females (with respect to prespawning and spawning periods). Xyrichtys novacula uses local food sources, as confirmed by d13C and d15N, and females and males use different food sources, thus avoiding intraspecific competition. This was confirmed by d15N enrichment as size increased. Spawning leads to special requirements for gonad maturation, which is reflected in the isotopic signatures for both sexes.
Distribution shifts of demersal fishes are important adaptive responses to warming oceans for species' persistence. Shifts are facilitated by factors such as adult movement and dispersal of pelagic ...larvae to normally cooler regions, where increasing ocean temperatures are now enhancing larval and juvenile survival. However, successful recruitment (i.e. larval settlement) at these new regions can be constrained by resource availability, specialisation (food, habitat) and ecological interactions (competition, predation). Evaluating the capacity or likelihood of a species to successfully shift or expand its range, provides information relevant to biodiversity conservation and fisheries management, and is particularly important for species with restricted ranges. Choerodon rubescens (Günther, 1862) is an exploited labrid endemic to ~1400km of the west Australian coastline, encompassing 13° of latitude and a 6°C temperature gradient. This region recently experienced a rapid warming event of ~3°C, which lasted 3months and mirrored ocean temperatures expected in the next 50years. Following this event, high levels of recruitment of C. rubescens occurred towards its southern, cooler distribution limit. Juvenile abundances were surveyed in this study to evaluate: (1) the effect of elevated temperatures on recruitment success across shallow water habitats spanning the species' distribution, (2) temporal variation in recruitment success in the typically cooler, southern part of its range and (3) ecological characteristics important to recruit survival, including habitat preferences, diet and behaviour. Juvenile C. rubescens were significantly more abundant at the margin between reef and sand and towards the cooler southern range end. Reef margin habitat provides access to shelter from predators within the reef and to sand-associated invertebrate prey in adjacent soft sediments, where most feeding activity occurred. Juveniles were abundant (0.3 to 4 fish/40m2) in reef margin habitats of the southern cooler region for three consecutive years, with individuals represented by multiple cohorts, indicating suitable environmental conditions for ongoing recruitment and survival. Juveniles at this habitat were able to compete effectively with other co-occurring labrids for invertebrate prey. As oceans warm, the number of recruits arriving and surviving beyond the existing cooler range limit will be dependent on factors such as successful spawning, larval delivery and survival, and availability of reef margin habitat with associated prey; these factors will determine the successful range shift or expansion of C. rubescens. We present an example of how range-wide spatiotemporal ecological studies of juvenile fish can identify range shift capacity and inform management adaptive to climate change.
•A marine heatwave influenced fish recruitment in a tropical-temperate overlap zone.•Choerodon rubescens recruited in greatest abundance at their southern range margin.•Water temperatures allowed ongoing recruitment and survival in that region.•Available reef-sand margins and invertebrate prey supported survival.•Understanding key biological characteristics is critical in changing environments.
Aim: To examine the dynamics among the processes of speciation, extinction and dispersal in marine environments using phylogenies to reveal the evolutionary mechanisms that promote latitudinal ...differences in biodiversity. Using phylogenetic comparative methods we assess whether tropical reef fish lineages show higher diversification rates and whether the majority of extratropical reef fish lineages have originated from tropical areas. Location: Shallow water tropical and extratropical reefs globally. Methods: Using fossil-calibrated phylogenies for four reef-associated fish families (Chaetodontidae, Labridae, Pomacentridae and Sparidae) we apply evolutionary models (GeoSSE and HiSSE) that allow the estimation of speciation, extinction and dispersal rates associated with geographical ranges and explore potential biases from unsampled characters. Results: We found that tropical lineages show higher rates of speciation and tended to have lower extinction rates. Overall, we identify higher net diversification rates for tropical lineages compared with those in extratropical regions in all four families. Rates of dispersal tended to be higher for lineages with tropical origins expanding into extratropical regions. Within the family Labridae, two tropical lineages were found to exhibit higher net diversification rates, above that expected from latitudinal differences. Main conclusions: Our results offer support for the predictions of the 'out of the tropics' and 'evolutionary speed' models of evolution, both of which highlight the marine tropics as an important evolutionary engine promoting latitudinal differences in reef fish biodiversity. Moreover, we find that two tropical labrid lineages are undergoing exceptional diversification associated with additional traits, possibly linked with the extreme sexual dichromatism observed in both clades.
Trophic cascades caused by a reduction in predators of sea urchins have been reported in Indian Ocean and Caribbean coral reefs. Previous studies have been constrained by their siteâspecific nature ...and limited spatial replication, which has produced site and speciesâspecific understanding that can potentially preclude larger communityâorganization nuances and generalizations. In this study, we aimed to evaluate the extent and variability of the cascade community in response to fishing across
Native prey can be particularly vulnerable to consumption by exotic predators. Prey naiveté, the failure to recognize a novel predator due to lack of recent co-evolutionary history, likely ...facilitates the disproportionate impact that some exotic predators exert on prey populations. Lionfish Pterois volitans, exotic predators from the Pacific, have invaded coral reefs and other coastal habitats along the western Atlantic. Prey naiveté towards novel lionfish was tested in field experiments and with observations using closest approach distance as the anti-predator response. We quantified the distance of prey fishes to exotic lionfish in both the Atlantic and Pacific (invasive and native ranges of lionfish) as well as to native predators in the Atlantic. In the Atlantic, experiments indicated that Haemulon plumierii, prey of lionfish, generally display a closer approach distance to exotic than to native predators, and field observations of free-ranging fish revealed that at least 5 other species of small fishes (Halichoeres bivitattus, Halichoeres garnoti, Scarus taeniopterus, Stegastes leucostictus and Thalassoma bifasciatum) also might exhibit limited predator-avoidance behaviour towards invasive lionfish. We also found that 3 families of small fish (Labridae, Pomacentridae and Scaridae) maintained greater distances from lionfish in the Pacific compared with the Atlantic in both experimental and field observations. These results suggest prey naiveté to exotic lionfish by at least 8 species of fish (Abudefduf saxatilis, H. plumierii, H. bivitattus, H. garnoti, S. taeniopterus, Sparisoma aurofrenatum, S. leucostictus and T. bifasciatum) in the Atlantic, which could be contributing to the rapid expansion of this invasive species by enhancing its fitness and reproductive output through high predation efficiency.
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