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For the last seven decades, cleaning symbiosis in the marine environment has been a research field of intrigue. There is substantial evidence that, by removing undesired items from their client fishes, cleaner organisms have positive ecosystem effects. These include increased fish recruitment, abundance and enhanced fish growth. However, the intimate association and high frequency of interactions between cleaners and clients potentially facilitates pathogen transmission and disease spread. In this review, we identify knowledge gaps and develop novel hypotheses on the interrelationship between parasites, hosts and the environment (disease triangle concept), with a particular emphasis on the potential role of cleaner organisms as hosts and/or transmitters of parasites. Despite evidence supporting the positive effects of cleaner organisms, we propose the cleaners as transmitters hypothesis; that some parasites may benefit from facilitated transmission to cleaners during cleaning interactions, or may use cleaner organisms as transmitters to infect a wider diversity and number of hosts. This cost of cleaning interactions has not been previously accounted for in cleaning theory. We also propose the parasite hotspot hypothesis; that parasite infection pressure may be higher around cleaning stations, thus presenting a conundrum for the infected client with respect to cleaning frequency and duration. The impact of a changing environment, particularly climate stressors on cleaners’ performance and clients’ cleaning demand are only beginning to be explored. It can be expected that cleaners, hosts/clients, and parasites will be impacted in different ways by anthropogenic changes which may disrupt the long-term stability of cleaning symbiosis.

Cleaner fish remove parasites from other organisms, called clients. While there is an extensive body of work on the positive role of cleaners for their clients and reef communities, remarkably, potential parasites hosted by specialised cleaner fishes themselves have not been explored. In this study, we surveyed the parasite community of the Indo-Pacific cleaner wrasse Labroides dimidiatus, and compared it to other wrasses from the same region. L. dimidiatus was found to be infected by eight parasite groups including ectoparasites (copepods, isopods, trichodinids, monogeneans and turbellarians) and endoparasites (myxozoans, trematodes and cestodes) representing at least 12 species. The abundance and prevalence of most parasite groups was comparable to other wrasses, with the exception of bucephalid trematodes, which are not known to infect any other tropical wrasses except for Labroides species. This adds to mounting evidence that some parasite species exhibit atypical life cycles that exploit cleaning symbiosis. Particularly noteworthy was the discovery of gnathiid isopods on L. dimidiatus, which are generally considered the cleaner’s primary food item. Our findings provide new evidence for a potential role of wild cleaner fish as vectors of parasites to new clients, which highlights potential costs associated with cleaning symbiosis.

Widespread coral mortality is leading to coral reef degradation worldwide. Many juvenile reef fishes settle on live coral, and their predator-avoidance behaviour is disrupted in seawater exposed to dead corals, ultimately increasing predation risk. Gnathiid isopods are micropredatory fish ectoparasites that occur in higher abundances in dead coral. However, the effect of seawater associated with dead coral on the susceptibility of fish to micropredators has never been investigated. We tested whether the infection rate of cultured gnathiid ectoparasites on individual damselfish, Pomacentrus amboinensis Bleeker 1868, from two different ontogenetic stages (juveniles and adults) was influenced by seawater exposed to three different treatments: dead coral, live coral, or no coral. Seawater treatments were presumed to contain different chemical properties and are meant to represent environmental changes associated with habitat degradation on coral reefs. Gnathiid infection of juvenile fish in seawater exposed to dead coral was twice as high as that of fish in live coral or no coral. Infection rates did not significantly differ between live coral and no coral treatments. In contrast to juveniles, the susceptibility of adults to gnathiids was not affected by seawater treatment. During experiments, juvenile fish mortality was relatively low, but was higher for infected fish (9.7%), compared to fish held without exposure to gnathiids (1.7%). No mortality occurred in adult fish that became infected with gnathiids. Our results suggest that chemical cues released from dead corals and/or dead coral colonisers affect the ability of juvenile, but not adult fish to avoid parasite infection. Considering increased habitat degradation on coral reefs and that gnathiids are more abundant in dead coral substrate, it is possible that wild juvenile fish may experience increased susceptibility to parasitic infection and reduced survival rate. This highlights the importance of including parasitism in ecological studies of global environmental change.

Gnathiid isopods, common fish ectoparasites, can affect fish physiology, behaviour and survival. Gnathiid juveniles emerge from the benthos to feed on fish blood. In the Caribbean, gnathiids are positively associated with dead coral and negatively associated with live coral, due to coral predation on gnathiids. However, such interactions were unstudied in the Great Barrier Reef (GBR). Due to recent extreme weather events (two cyclones and one mass warm-water coral bleaching event, 2014–2016), it is now urgent to understand the role of corals on the abundance of these ectoparasites. Here, to understand parasite–coral dynamics at the micro-habitat level, we examined substrate associations of gnathiid isopods on Lizard Island (GBR) using demersal plankton emergence traps. Additionally, we determined whether two abundant hard coral species, Goniopora lobata and Pocillopora damicornis, predate on gnathiids in a laboratory experiment using containers with gnathiids and fragments from each coral species or dead coral as controls. The abundance of gnathiids over natural substrates was higher for dead compared to live hard coral and sand, but not live soft coral. Moreover, we found that free-swimming gnathiids decreased in containers with live coral compared to dead coral controls. This was attributed to predation as we also directly observed a coral ingesting a gnathiid. Our results suggest that dead coral is a suitable microhabitat for gnathiids, but that live coral is not since live corals can predate on gnathiids. We propose that following extreme events, such as cyclones and heat waves, gnathiids might benefit from more dead coral substrate and a decrease in predation by the reduction in coral cover on the reef. We advocate that an increase in the frequency of extreme events may have cascading effects for the fish population through changes in the population of benthos-dependent ectoparasites.

Cleaner fishes are key contributors to the health of fish communities. However, much of the information in the literature refers to tropical systems, while fewer studies have examined the activity of cleaner fish inhabiting temperate ecosystems. Facultative cleaner fish are assumed to clean only during their juvenile phase, and have a broader diet than obligatory cleaner fish. Here, we focused on 2 facultative cleaner fish species, Coris julis and Thalassoma pavo, that live along the temperate coasts of the Azorean island of São Miguel. We found that these species focused their cleaning activities on relatively few species of clients, which supports the general idea that facultative cleaner fishes in temperate waters are less dependent on cleaning interactions than obligatory cleaner fishes in tropical waters. Both cleaner species were found to give more bites per host when inspecting larger clients, likely because the latter typically host more parasites. We found that C. julis consumed a greater diversity of food items, which included gnathiid larvae and fewer caligid copepods, compared to T. pavo where no ectoparasites were found. All cleaner fish that we collected after observations of cleaning had eaten gnathiid isopod larvae but not caligid copepods, even though caligid copepods were the most abundant ectoparasite found on the body of 7 selected fish species (including both client and non-client species), suggesting that both species selectively feed on gnathiid isopods. This study is the first to demonstrate that temperate facultative cleaner fish species actively and selectively inspect and remove ectoparasites from their client-fish species.

O comportamento das espécies de peixes limpadores facultativos de águas temperadas, só recentemente começou a ser estudado ao contrário do que sucede em águas tropicais. Duas espécies de labrídeos, Coris julis e Thalassoma pavo, são caracterizadas como limpadoras nas águas costeiras dos Açores, mas pouco se sabe sobre as suas interacções mutualísticas. Com vista a colmatar esta lacuna, este trabalho analisa o comportamento destas duas espécies de peixes limpadores e dos seus peixes visitantes (referidos como “clientes”) aos seus territórios fixos (referidos como “estações de limpeza”), comparando a frequência das suas interacções com aquelas observadas em locais não fixos e no sentido de determinar: a) qual a dependência dos limpadores relativamente às suas actividades mutualísticas, e b) o impacto do seu comportamento nos níveis de infestação da sua “clientela”.Depois de se ter confirmado a existência de “estações de limpeza” nas costas da Ilha de São Miguel, dez estações de limpeza envolvendo C. julis e dez envolvendo T. pavo foram definidas, contabilizando-se um total de 600 min de observações. Para além disso, fora das “estações de limpeza”, 13 observações foram feitas para C. julis e cinco para T. pavo num total de 540 min de observações. Todas as observações foram feitas durante 30 min. Foram capturados aleatoriamente (fora do contexto de limpeza) trinta C. julis e trinta T. pavo, assim como três C. julis e dois T. pavoconsiderados como limpadores (no contexto de limpeza) presentes nas suas “estações de limpeza”, para posterior análise dos seus conteúdos estomacais. No sentido de determinar o nível de infestação parasitária foram capturados um total de 77 indivíduos pertencentes a oito espécies diferentes de “clientes” e “controlos” (Symphodus caeruleus, Sparisoma cretense, Abudefduf luridus, Sarpa salpa, Labrus bergylta, Mullus surmuletus, Serranus atricauda e Diplodus sargus) que se encontravam nas imediações das “estações de limpeza”.Dentro das estações de limpeza, foram observadas mais interacções entre T. pavo e os seus “clientes” (12, 4 ± 2,3) do que C. julis (10, 7 ± 1,3), enquanto fora das “estações de limpezas” ocorreu o inverso (C. julis: 3 ± 1,8; T. pavo: 1,75 ± 0,8). No conjunto de todas as observações comportamentais das duas espécies de limpadores, não foram encontradas diferenças significativas na diversidade específica dos seus “clientes”, contabilizando um total de sete espécies, seis destas observadas como “clientes” de C. julis (S. caeruleus, S. cretense, A. luridus, L. bergylta, M. surmuletus e C. julis) e quatro de T. pavo (S. caeruleus, S. cretense, S. salpa, L. bergylta), sendo a espécie S. caeruleus o “cliente” dominante no total das interacções de limpeza. Maior parte dos “clientes” foram observados a iniciar as interacções de limpeza adoptando uma postura específica (78,9 %), sendo estas interacções normalmente terminadas pelos limpadores (81,9 %). Uma correlação significativamente positiva foi encontrada entre o número de toques e a área dos peixes “clientes” para ambas as espécie de limpadores, mas a espécie T. pavo passou significativamente mais tempo com os “clientes” maiores, enquanto para C. julis nenhuma relação foi encontrada. Para além disso, T. pavo fez esperar os seus “clientes” significativamente mais tempo do que C. julis e no que toca aos seus níveis de cooperação com a espécie “cliente” S. caeruleus, o limpador C. julis provocou significativamente mais “jolts” (medida comportamental de desonestidade por parte do limpador) em comparação a T. pavo. Foram encontradas diferenças significativas na dieta geral entre C. julis e T. pavo capturados aleatoriamente. O item crustáceos dominou a dieta de ambas as espécies mas demonstrou-se mais importante para a espécie T. pavo, enquanto ectoparasitas (larvas de gnatídeos) foram exclusivamente encontrados na dieta de C. julis. Comparando a dieta de C. julis e T. pavo capturados aleatoriamente com os limpadores, observou-se diferenças onde os limpadores alimentam-se quase exclusivamente de ectoparasitas e apresentaram muco (dois C. julis), enquanto as semelhanças se centralizaram na presença de escamas nos seus conteúdos estomacais. Foram também encontradas diferenças significativas na carga parasitária de todas espécies caracterizadas como “clientes” (S. caeruleus, S. cretense, A. luridus, S. salpa, L. bergylta, M. surmuletus) e “controlos” (S. atricauda, D. sargus), revelando uma dominância de ectoparasitas da família Caligidae em comparação a Gnathiidae. Ainda esta carga parasitária não se mostrou positivamente relacionada com as respectivas áreas corporais dos “clientes” e “controlos”.

Since microorganisms play a major role in the biogeochemistry of the ocean, understanding structure and dynamics of natural microbial communities is crucial in assessing the impact of environmental changes on marine ecosystems. In order to identify key environmental drivers of microbial community structure in Chilean Patagonian fjords, we analyzed composition of the prokaryotic community over an annual cycle at a single sampling site in Puyuhuapi Fjord. Distinctive communities represented mainly by Actinomycetales, Rhodobacteraceae, Cryomorphaceae and Flavobacteriaceae were associated with Estuarine Fresh Waters, whereas Cenarchaeaceae and Oceanospirillales were representative of Modified Sub Antarctic Waters present in the fjord. Salinity and oxygen were first-order factors explaining segregation of microbial communities in these contrasting water masses. Positive correlations of members of Flavobacteriaceae, Alteromonadales and Verrucomicrobiales with diatoms in subsurface waters and of Flavobacteriales (Cryomorphaceae and Flavobacteriaceae), Rhodobacteraceae and Pelagibacteraceae with dinoflagellates in surface waters suggest that phytoplankton composition could define specific niches for microorganisms in Puyuhuapi fjord waters. A dramatic reduction of richness and individual abundances within Flavobacteriaceae, Rhodobacteraceae and Cenarchaeaceae families was principally explained by seasonal increase of surface water temperature, with major reduction associated with changes in temperature during winter conditions. Taxa that are sensitive to increased temperature are key components of organic matter and element cycling, and we therefore suggest that potential decrease in diversity associated with rising of surface water temperature could impact current biogeochemical status of Patagonian fjord ecosystems.

[...]there are stories that American folkloristics has told about Canada-and establishing how those stories have changed. Because we cannot assume that all JAF readers are familiar with all of these stories, we will try to detail their basic structures as well as to critique them (or refer to locations where readers may learn for themselves). [...]there are individuals reflecting, often from personal recollection but also frequently based on field research as well, on traditions from their own heritage. A few strongly bilingual individuals acted as cultural brokers, but there was little expectation for cooperation or interaction between MUN and Laval-primarily because the Anglophones felt uncomfortable in French, but also because they did not feel that the scholarship from Laval was relevant to their own work.17 While recent collaborative projects promise fruitful results, these new developments are not reflected in this special issue.18 As well as an absence of French work, we might note the absence of the mainstream of Quebecois folklore/ethnology studies, which Turgeon and others characterize as \"a genealogical construct to reinforce the idea of a common French heritage. . A collection of articles on folklore published in the Journal of Canadian Studies included one MUN Folklore Department faculty member (Neil V. Rosenberg), one MUN student (Mark Ferguson), faculty in other programs (Gary Butler, Humanities Program at York University; Pauline Greenhill, Women's Studies at the University of Winnipeg; and Diane Tye, then Canadian Studies at Mount Allison University), two Laval University Ethnology faculty (Lucille Guilbert and Jean Simard), one Laval student (Christiane Noel), a museum worker (Yves Bergeron, of the Musee de l'Amerique francaise), and a Canadian-born, American-trained scholar working in the United States but focusing upon her own family's heritage (Luisa del Giudice) (Butler and Greenhill 1994). Greenhill similarly shows media effects on the transmission of concepts of race and whiteness in the \"English male dance tradition\" of Morris, and Robidoux's work considers how specific native traditions have influenced Canadian sport-and how those sports move back into First Nations communities.