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Multidisciplinary approaches to conservation and wildlife management are often effective in addressing complex, multi-factor problems. Emerging fields such as conservation physiology and conservation behaviour can provide innovative solutions and management strategies for target species and systems. Sensory ecology combines the study of 'how animals acquire' and process sensory stimuli from their environments, and the ecological and evolutionary significance of 'how animals respond' to this information. We review the benefits that sensory ecology can bring to wildlife conservation and management by discussing case studies across major taxa and sensory modalities. Conservation practices informed by a sensory ecology approach include the amelioration of sensory traps, control of invasive species, reduction of human-wildlife conflicts and relocation and establishment of new populations of endangered species. We illustrate that sensory ecology can facilitate the understanding of mechanistic ecological and physiological explanations underlying particular conservation issues and also can help develop innovative solutions to ameliorate conservation problems.

Animal microbiomes play an important role in dietary adaptation, yet the extent to which microbiome changes exhibit parallel evolution is unclear. Of particular interest is an adaptation to extreme diets, such as blood, which poses special challenges in its content of proteins and lack of essential nutrients. In this study, we assessed taxonomic signatures (by 16S rRNA amplicon profiling) and potential functional signatures (inferred by Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt)) of haematophagy in birds and bats. Our goal was to test three alternative hypotheses: no convergence of microbiomes, convergence in taxonomy and convergence in function. We find a statistically significant effect of haematophagy in terms of microbial taxonomic convergence across the blood-feeding bats and birds, although this effect is small compared to the differences found between haematophagous and non-haematophagous species within the two host clades. We also find some evidence of convergence at the predicted functional level, although it is possible that the lack of metagenomic data and the poor representation of microbial lineages adapted to haematophagy in genome databases limit the power of this approach. The results provide a paradigm for exploring convergent microbiome evolution replicated with independent contrasts in different host lineages. This article is part of the theme issue 'Convergent evolution in the genomics era: new insights and directions'.

Hearing ability is well studied across teleost fishes in general, and vertebrates more broadly, but little is known about sound detection abilities of lampreys (Petromyzontiformes), a basal extant vertebrate group. The sea lamprey (Petromyzon marinus) is a destructive invader of the Laurentian Great Lakes, while numerous lamprey species (including the sea lamprey) are imperiled in their native ranges. In both management scenarios, behavioral manipulation tactics to control movement and distribution are desired. Therefore, we describe the hearing ability and behavioral responses of adult and juvenile sea lamprey to sound to reveal how hearing may have evolved in vertebrates and determine possible management applications. Based on auditory evoked potentials, sea lamprey detected tones of 50-300 Hz with equal sensitivity, but did not detect sounds above 300 Hz. In a laboratory bioassay, sea lamprey behaviorally responded to sound range of 50-200 Hz, with a general increase in swimming and a decrease in resting behaviours at both juvenile and adult stages relative to no-sound controls. To our knowledge, this is the first test of lamprey hearing, and the results support that sound may be a means to modify lamprey behaviour for management purposes. La capacite auditive est bien etudiee chez les poissons teleosteens en general, et plus largement chez les vertebres, mais les connaissances sur les capacites de detection des sons par les lamproies (Petromyzontiformes), un groupe basal de vertebres vivant aujourd'hui, sont limitees. La grande lamproie marine (Petromyzon marinus) est une espece envahissante destructrice dans les Grands Lacs laurentiens, alors que de nombreuses especes de lamproies (dont la grande lamproie marine) sont en peril dans leurs aires de repartition indigenes. Dans les deux scenarios de gestion, de methodes de manipulation du comportement visant a controler les deplacements et la repartition sont souhaitables. Nous decrivons donc la capacite auditive et les reactions comportementales au son de grandes lamproies marines adultes et juveniles afin d'etablir comment l'ouie pourrait avoir evolue chez les vertebres et de cerner des applications possibles en gestion. A la lumiere des potentiels evoques auditifs, les grandes lamproies marines detectent des tons de 50 a 300 Hz avec la meme sensibilite, mais ne detectent pas les sons de plus de 300 Hz. Dans le cadre d'une epreuve biologique en laboratoire, de grandes lamproies marines modifiaient leur comportement en reponse a des sons de 50 a 200 Hz, l'activite de nage etant accrue et les comportements de repos diminuant chez les adultes comme chez les juveniles par rapport aux temoins non exposes a des sons. A notre connaissance, il s'agit du premier essai sur l'ouie des lamproies, et les resultats appuient l'interpretation voulant que le son puisse permettre de modifier leur comportement pour les fins de la gestion. [Traduit par la Redaction], Introduction Sound is an important sensory modality for fish and is commonly used for predator-prey detection, courtship-mating, and alarm cues (Fay and Popper 2000; van der Sluijs et al. 2011). [...]

Abstract Background Vertebrate pheromones are known to prime the endocrine system, especially the hypothalamic-pituitary-gonadal (HPG) axis. However, no known pheromone molecule has been shown to modulate directly the synthesis or release of gonadotropin releasing hormone (GnRH), the main regulator of the HPG axis. We selected sea lamprey (Petromyzon marinus) as a model system to determine whether a single pheromone component alters the output of GnRH.Sea lamprey male sex pheromones contain a main component, 7α, 12α, 24-trihydroxy-5α-cholan-3-one 24-sulfate (3 keto-petromyzonol sulfate or 3kPZS), which has been shown to modulate behaviors of mature females. Through a series of experiments, we tested the hypothesis that 3kPZS modulates both synthesis and release of GnRH, and subsequently, HPG output in immature sea lamprey. Results The results showed that natural male pheromone mixtures induced differential steroid responses but facilitated sexual maturation in both sexes of immature animals (χ2 = 5.042, dF = 1, p < 0.05). Exposure to 3kPZS increased plasma 15α-hydroxyprogesterone (15α-P) concentrations (one-way ANOVA, p < 0.05) and brain gene expressions (genes examined: three lamprey (l) GnRH-I transcripts, lGnRH-III, Jun and Jun N-terminal kinase (JNK); one-way ANOVA, p < 0.05), but did not alter the number of GnRH neurons in the hypothalamus in immature animals. In addition, 3kPZS treatments increased lGnRH peptide concentrations in the forebrain and modulated their levels in plasma. Overall, 3kPZS modulation of HPG axis is more pronounced in immature males than in females. Conclusions We conclude that a single male pheromone component primes the HPG axis in immature sea lamprey in a sexually dimorphic manner.

Haematopoietic stem and progenitor cells (HSPCs) require a specific microenvironment, the haematopoietic niche, which regulates HSPC behaviour.sup.1,2. The location of this niche varies across species, but the evolutionary pressures that drive HSPCs to different microenvironments remain unknown. The niche is located in the bone marrow in adult mammals, whereas it is found in other locations in non-mammalian vertebrates, for example, in the kidney marrow in teleost fish. Here we show that a melanocyte umbrella above the kidney marrow protects HSPCs against ultraviolet light in zebrafish. Because mutants that lack melanocytes have normal steady-state haematopoiesis under standard laboratory conditions, we hypothesized that melanocytes above the stem cell niche protect HSPCs against ultraviolet-light-induced DNA damage. Indeed, after ultraviolet-light irradiation, unpigmented larvae show higher levels of DNA damage in HSPCs, as indicated by staining of cyclobutane pyrimidine dimers and have reduced numbers of HSPCs, as shown by cmyb (also known as myb) expression. The umbrella of melanocytes associated with the haematopoietic niche is highly evolutionarily conserved in aquatic animals, including the sea lamprey, a basal vertebrate. During the transition from an aquatic to a terrestrial environment, HSPCs relocated into the bone marrow, which is protected from ultraviolet light by the cortical bone around the marrow. Our studies reveal that melanocytes above the haematopoietic niche protect HSPCs from ultraviolet-light-induced DNA damage in aquatic vertebrates and suggest that during the transition to terrestrial life, ultraviolet light was an evolutionary pressure affecting the location of the haematopoietic niche.Melanocytes above the haematopoietic niche protect haematopoietic stem cells from ultraviolet-light-induced DNA damage in aquatic vertebrates throughout evolution; this niche moved to the bone marrow during the transition to terrestrial life., Author(s): Friedrich G. Kapp [sup.1] [sup.2] [sup.3] , Julie R. Perlin [sup.1] [sup.2] , Elliott J. Hagedorn [sup.1] [sup.2] , John M. Gansner [sup.4] , Daniel E. Schwarz [sup.5] , [...]

By investigating historic trapping records of invasive sea lamprey (Petromyzon marinus) throughout tributaries to the Laurentian Great Lakes, we found that upstream spawning migration timing was highly correlated with stream temperatures over large spatial and temporal scales. Furthermore, several streams in our study exceeded a critical spring thermal threshold (i.e., 15[degrees]C) and experienced peak spawning migration up to 30 days earlier than in the 1980s, whereas others were relatively unchanged. Streams exhibiting warming trends and earlier migration were spatially clustered and generally found on the leeward side of the Great Lakes where the lakes most affect local climate. These findings highlight that all streams are not equally impacted by climate change and represent, to our knowledge, the first observation linking long-term changes in stream temperatures to shifts in migration timing of an invasive fish. Earlier sea lamprey migration in Great Lakes tributaries may improve young of the year growth and survival but not limit their spatial distribution, making sea lamprey control more challenging. L'etude des registres de piegeage de lamproies (Petromyzon marinus) envahissantes dans les affluents des Grands Lacs laurentiens permet d'etablir que le moment de la migration de frai vers l'amont est fortement correle aux temperatures des cours d'eau a de grandes echelles spatiales et temporelles. En outre, plusieurs cours d'eau etudies depassent le seuil de temperature printaniere critique (c.-a-d. 15[degrees]C), et la pointe de la migration de frai y a lieu jusqu'a 30 jours plus tot que dans les annees 1980, alors que d'autres cours d'eau montrent relativement peu de changement. Les cours d'eau qui presentent des tendances au rechauffement et une migration plus precoce sont regroupes dans l'espace et se trouvent generalement du cote sous le vent des Grands Lacs, la ou l'incidence des lacs sur le climat local est la plus forte. Ces constatations soulignent le fait que les changements climatiques n'ont pas la meme incidence sur tous les cours d'eau et elles constituent, a notre connaissance, la premiere observation d'un lien entre les variations a long terme de la temperature des cours d'eau et des changements du moment de la migration d'un poisson envahissant. La migration plus precoce des lamproies dans des affluents des Grands Lacs pourrait ameliorer la croissance et la survie des jeunes de l'annee, sans toutefois limiter leur repartition spatiale, rendant ainsi le controle des lamproies plus difficile. [Traduit par la Redaction], Introduction Global climate change has had increasingly strong effects on environmental patterns during the past several decades (Dale et al. 2001; Vaughan et al. 2003; Chen et al. 2006). In [...]

Two sounds associated with spawning lake trout (Salvelinus namaycush) in lakes Huron and Champlain were characterized by comparing sound recordings with behavioral data collected using acoustic telemetry and video. These sounds were named 'growls' and 'snaps' and were heard on lake trout spawning reefs, but not on a nonspawning reef, and were more common at night than during the day. Growls also occurred more often during the spawning period than the prespawning period, while the trend for snaps was reversed. In a laboratory flume, sounds occurred when male lake trout were displaying spawning behaviors: growls when males were quivering and parallel swimming and snaps when males moved their jaw. Combining our results with the observation of possible sound production by spawning splake (Salvelinus fontinalis x Salvelinus namaycush hybrid) provides rare evidence for spawning-related sound production by a salmonid or any other fish in the superorder Protacanthopterygii. Further characterization of these sounds could be useful for lake trout assessment, restoration, and control. Deux sons associes aux touladis (Salvelinus namaycush) en frai dans les lacs Huron et Champlain sont caracterises en comparant des enregistrements sonores a des donnees comportementales recueillies par telemetrie acoustique et par video. Ces sons, designes << grognements >> et << craquements >>, ont ete entendus sur des recifs de frai de touladis, mais non sur un recif non utilise pour le frai, et ils etaient plus frequents la nuit que le jour. Les grognements se produisaient egalement plus souvent durant la periode de frai que durant la periode precedant le frai, alors que le contraire etait vrai pour les craquements. Dans un canal experimental en laboratoire, des sons se produisaient quand des touladis males affichaient des comportements de frai; des grognements quand les males fremissaient et nageaient en parallele et des craquements quand les males faisaient bouger leurs machoires. La combinaison de nos resultats avec l'observation de la production possible de sons par de truites moulacs (hybrides Salvelinus fontinalis x Salvelinus namaycush) en frai fournit une rare preuve de la production de sons associee au frai par un salmonide ou tout autre poisson du superordre des Protacanthopterygii. Une caracterisation plus approfondie de ces sons pourrait etre utile pour l'evaluation, le retablissement et le controle des touladis. [Traduit par la Redaction], Introduction Lake trout (Salvelinus namaycush) interest biologists and fishery managers worldwide because of their extraordinary diversity (Muir et al. 2015), recreational and commercial importance (Muir et al. 2013), and invasiveness [...]

Rapid evolution of pest, pathogen, and wildlife populations can have undesirable effects, for example, when insects evolve resistance to pesticides or fishes evolve smaller body size in response to harvest. A destructive invasive species in the Laurentian Great Lakes, the sea lamprey (Petromyzon marinus) has been controlled with the pesticide 3-trifluoromethyl-4-nitrophenol (TFM) since the 1950s. We evaluated the likelihood of sea lamprey evolving resistance to TFM by (i) reviewing sea lamprey life history and control; (ii) identifying physiological and behavioural resistance strategies; (iii) estimating the strength of selection from TFM; (iv) assessing the timeline for evolution; and (v) analyzing historical toxicity data for evidence of resistance. The number of sea lamprey generations exposed to TFM was within the range observed for fish populations where rapid evolution has occurred. Mortality from TFM was estimated as 82%-90%, suggesting significant selective pressure. However, 57 years of toxicity data revealed no increase in lethal concentrations of TFM. Vigilance and the development of alternative controls are required to prevent this aquatic invasive species from evolving strategies to evade control. Resume : L'evolution rapide de populations d'organismes nuisibles, de pathogenes et d'animaux sauvages peut avoir des effets indesirables comme, par exemple, des insectes qui developpent une resistance aux pesticides ou une diminution de la taille du corps des poissons en reponse a la peche. Le pesticide 3-trifluoromethyl-4-nitrophenol (TFM) est utilise depuis les annees 1950 pour lutter contre la lamproie (Petromyzon marinus), une espece envahissante destructrice dans les Grands Lacs laurentiens. Nous avons evalue la probabilite que les lamproies developpent une resistance au TFM par (i) l'examen du cycle biologique des lamproies et des methodes de lutte contre cette espece, (ii) la determination des strategies de resistance physiologiques et comportementales (iii) l'estimation de la force de la selection decoulant du TFM, (iv) revaluation de la duree necessaire pour qu'il y ait evolution et (v) l'analyse de donnees historiques sur la toxicite pour voir s'il existe des indices de resistance. Le nombre de generations de lamproies exposees au TFM est dans la fourchette observee pour les populations de poissons ayant subi une evolution rapide. La mortalite causee par le TFM est estimee a 82-90 %, ce qui indiquerait une pression de selection significative. Cependant, 57 annees de donnees sur la toxicite ne revelent aucune augmentation des concentrations letales de TFM. La vigilance et la mise au point d'autres mesures de lutte sont necessaries pour empecher cette espece aquatique envahissante de developper des strategies lui permettant de contrer les efforts de lutte. [Traduit par la Redaction], Introduction The capability of pathogens and pests to evolve resistance to control measures is a global concern with implications for human health, natural resource management, and agriculture (Palumbi 2001). Resistance [...]

Chemoreception is hypothesized to influence spawning site selection, mate search, and synchronization of gamete release in chars (Salvelinus spp.), but behavioral evidence is generally lacking. Here, we provide a survey of the behavioral responses of reproductive male and female lake trout (Salvelinus namaycush) to natural conspecific chemosensory stimuli. A flow-through laboratory assay with side-by-side artificial spawning reefs was used to evaluate behavioral preferences of spawning-phase males and females for chemosensory stimuli from juveniles and from spawning-phase males and females. Males and females preferred male and juvenile stimuli over no stimuli, but only had weak preferences for female stimuli. Only females had a preference for male over juvenile stimuli when given a direct choice between the two. The unexpected observation of male attraction to male stimuli, even when offered female stimuli, indicates a fundamental difference from the existing models of chemical communication in fishes. We discuss our results from the perspectives of prespawning aggregation, mate evaluation, and spawning synchronization. Identification of specific components of the stimuli will allow confirmation of the function and may have management implications for native and invasive populations of lake trout that are ecologically and economically important. S'il a ete postule que la chimioreception influencerait le choix des sites de frai, la recherche d'un compagnon et la synchronisation de la liberation de gametes chez les ombles (Salvelinus spp.), peu de preuves comportementales appuient ces postulats. Nous presentons une evaluation des reactions comportementales de touladis (Salvelinus namaycush) males et femelles reproducteurs a des stimuli chimiosensoriels naturels provenant de conspecifiques. Un essai en ecoulement continu en laboratoire avec des recifs de frai artificiels contigus a ete utilise pour evaluer les preferences comportementales de males et femelles en phase de frai pour des stimuli chimiosensoriels provenant de juveniles et de males et femelles en phase de frai. Les males et les femelles preferaient les stimuli des males et des juveniles a l'absence de stimulus, mais ne presentaient que de faibles preferences pour les stimuli des femelles. Seules les femelles avaient une preference pour les stimuli des males plutot que des juveniles quand elles etaient en presence d'un choix direct entre les deux. L'observation non prevue d'une attraction exercee par les stimuli de males sur les males, meme en presence de stimuli de femelles, indique une divergence fondamentale par rapport aux modeles existants deja de communication chimique chez les poissons. Nous discutons de nos resultats des points de vue du regroupement avant le frai, de l'evaluation des compagnons et de la synchronisation du frai. L'identification de composantes specifiques des stimuli permettra d'en confirmer la fonction et pourrait s'averer pertinente pour la gestion de populations de touladis indigenes et envahissantes d'importance ecologique et economique. [Traduit par la Redaction], Introduction The evolution and ecology of chars (Salvelinus spp.) garners broad scientific interest (Muir et al. 2015) and has conservation implications for aquatic ecosystems throughout the world (Crossman 1995; Zimmerman [...]

The sea lamprey Petromyzon marinus is an invasive pest in the Laurentian Great Lakes basin, threatening the persistence of important commercial and recreational fisheries. There is substantial interest in developing effective trapping practices via the application of behavior-modifying semiochemicals (odors). Here we report on the effectiveness of utilizing repellent and attractant odors in a push-pull configuration, commonly employed to tackle invertebrate pests, to improve trapping efficacy at permanent barriers to sea lamprey migration. When a half-stream channel was activated by a naturally derived repellent odor (a putative alarm cue), we found that sea lamprey located a trap entrance significantly faster than when no odor was present as a result of their redistribution within the stream. The presence of a partial sex pheromone, acting as an attractant within the trap, was not found to further decrease the time to when sea lamprey located a trap entrance relative to when the alarm cue alone was applied. Neither the application of alarm cue singly nor alarm cue and partial sex pheromone in combination was found to improve the numbers of sea lamprey captured in the trap versus when no odor was present--likely because nominal capture rate during control trials was unusually high during the study period. Behavioural guidance using these odors has the potential to both improve control of invasive non-native sea lamprey in the Great Lakes as well as improving the efficiency of fish passage devices used in the restoration of threatened lamprey species elsewhere. La lamproie marine Petromyzon marinus est une espece nuisible envahissante dans le bassin des Grands Lacs laurentiens, menacant la persistance d'importantes peches commerciales et sportives. L'elaboration de pratiques de piegeage efficaces par l'application de substances semiochimiques (odeurs) qui modifient le comportement suscite un interet considerable. Nous faisons etat de l'efficacite de l'utilisation d'odeurs repulsives et attractives dans une configuration de detournement stimulodissuasif (<< push-pull >>), communement employee dans la lutte contre les especes nuisibles invertebrees, pour ameliorer l'efficacite du piegeage a l'emplacement de barrieres permanentes a la migration des lamproies marines. Quand la moitie du chenal d'un cours d'eau est activee par une odeur repulsive d'origine naturelle (un signal d'alarme putatif), nous constatons que les lamproies marines se placent a l'entree du piege significativement plus vite que quand il n'y a pas d'odeur, en raison de leur redistribution rapide dans le cours d'eau. La presence d'une pheromone sexuelle partielle agissant comme substance attractive dans le piege ne reduit pas le temps requis pour que les lamproies se placent a l'entree du piege par rapport a la situation oU seul le signal d'alarme est applique. Il n'est pas observe que l'application du signal d'alarme seul, ni d'une combinaison du signal d'alarme et de la pheromone sexuelle partielle augmente le nombre de lamproies marines capturees dans le piege par rapport a la situation oU aucune odeur n'est presente, vraisemblablement en raison du fait que le taux de capture nominal durant les essais controles etait inhabituellement eleve durant la periode d'etude. L'orientation du comportement a l'aide de ces odeurs pourrait ameliorer la lutte contre la lamproie marine, une espece envahissante non indigene dans les Grands Lacs, ainsi que l'efficacite des passes a poissons utilisees pour le retablissement d'especes de lamproies menacees dans d'autres endroits. [Traduit par la Redaction], Introduction The Laurentian Great Lakes are highly susceptible to the establishment of invasive species, and of the approximately 180 nonnative species currently recognized in this region, the sea lamprey Petromyzon [...]

Improved methods are needed to evaluate barriers and traps for control and assessment of invasive sea lamprey (Petromyzon marinus) in the Great Lakes. A Bayesian state-space model provided reach-specific probabilities of movement, including trap capture and dam passage, for 148 acoustic tagged invasive sea lamprey in the lower Cheboygan River, Michigan, a tributary to Lake Huron. Reach-specific movement probabilities were combined to obtain estimates of spatial distribution and abundance needed to evaluate a barrier and trap complex for sea lamprey control and assessment. Of an estimated 21828 29 300 adult sea lampreys in the river, 0%-2%, or 0-514 untagged lampreys, could have passed upstream of the dam, and 46%- 61% were caught in the trap. Although no tagged lampreys passed above the dam (0/148), our sample size was not sufficient to consider the lock and dam a complete barrier to sea lamprey. Results also showed that existing traps are in good locations because 83%-96% of the population was vulnerable to existing traps. However, only 52%-69% of lampreys vulnerable to traps were caught, suggesting that traps can be improved. The approach used in this study was a novel use of Bayesian state- space models that may have broader applications, including evaluation of barriers for other invasive species (e.g., Asian carp (Hypophthalmichthys spp.)) and fish passage structures for other diadromous fishes. Il est necessaire d'ameliorer les methodes d'evaluation des barrieres et pieges utilises pour controler et evaluer la lamproie marine (Petromyzon marinus), une espece envahissante, dans les Grands Lacs. Un modele bayesien d'espace d'etats a produit des probabilites de deplacement, dont le piegeage et le passage de barrage, dans differents biefs pour 148 lamproies marines envahissantes dotees de marques acoustiques dans le cours inferieur de la riviere Cheboygan (Michigan), un affluent du lac Huron. Les probabilites de deplacement propres au bief ont ete combinees pour obtenir les estimations de la repartition spatiale et de l'abondance requises pour evaluer un complexe de barriere et piege pour le controle et l'evaluation des lamproies. Sur un nombre estime de 21828 a 29 300 lamproies adultes dans la riviere, de 0 % a 2 % des lamproies non marquees, soit de 0 a 514 poissons, pourraient etre passees en amont du barrage, et de 46 % a 61 % ont ete prises dans le piege. Bien qu'aucune lamproie marquee ne soit passee en amont du barrage (0/148), la taille de l'echantillon est trop petite pour permettre d'etablir que l'ecluse-barrage constitue une barriere completement etanche au passage des lamproies. Les resultats ont egalement demontre que les pieges existants sont bien situes, puisque de 83 % a 96 % de la population etait vulnerable aux pieges existants. Cependant, de 52 % a 69 % seulement des lamproies vulnerables aux pieges ont ete capturees, indiquant que ces pieges peuvent etre ameliores. L'approche employee constitue une utilisation novatrice des modeles bayesiens d'espace d'etats qui pourrait avoir des applications plus larges, notamment pour l'evaluation des barrieres au passage d'autres especes envahissantes (p. ex. carpe asiatique (Hypophthalmichthys spp.)) et des passes a poissons pour d'autres especes diadromes. [Traduit par la Redaction], Introduction The Laurentian Great Lakes were severely disrupted by the arrival of invasive sea lamprey (Petromyzon marinus) through the Welland Canal in the early 1900s (Smith and Tibbles 1980; Hansen [...]

Sea lamprey (Petromyzon marinus) avoid damage-released and predator chemosensory cues at night, but their response to these cues during the day is unknown. Here, we explored (i) whether sea lamprey avoid these cues during the day and (ii) the effect of water temperature on the avoidance of chemosensory alarm cues in two diurnal laboratory experiments. We hypothesized that daytime activity would be temperature-dependent and that only sea lamprey vulnerable to predation (i.e., not hiding) would behaviourally respond to chemosensory alarm cues. Ten groups of ten sea lamprey were exposed to one of a variety of potential chemosensory cues. The experiments were conducted over a range of temperatures to quantify the effect of temperature on avoidance behaviour. Consistent with our hypothesis, a higher proportion of animals were active during daytime as water temperature increased. Moving sea lamprey showed an avoidance response to 2-phenylethylamine (a compound found in mammalian urine) and human saliva once water temperatures had risen to mean (±SD) = 13.7 (± 1.4)°C. Resting and hiding sea lamprey did not show an avoidance response to any of the experimental stimuli. Pendant la nuit, les lamproies (Petromyzon marinus) evitent les signaux chimiosensoriels de predateurs ou liberes en cas de dommages, mais leur reaction a ces signaux durant le jour n'est pas connue. Nous tentons de determiner (i) si les lamproies evitent ces signaux durant le jour et (ii) l'effet de la temperature de l'eau sur l'evitement de signaux d'alarme chimiosensoriels dans le cadre de deux experiences diurnes en laboratoire. Nous avons postule que l'activite diurne depend de la temperature et que seules les lamproies vulnerables a la predation (c.-a-d. non cachees) adaptent leurs comportements en reaction a des signaux d'alarme chimiosensoriels. Dix groupes de dix lamproies ont ete exposes a un signal chimiosensoriel precis choisi parmi divers signaux possibles. Les experiences ont ete menees sur une fourchette de temperatures afin de quantifier l'effet de la temperature sur le comportement d'evitement. Conformement a notre hypothese, une plus grande proportion d'animaux etaient actifs durant le jour a mesure que la temperature augmentait. Les lamproies en mouvement presentaient une reaction d'evitement a la 2-phenylethylamine (un compose present dans l'urine de mammiferes) et a la salive humaine, une fois que la temperature de l'eau etait superieure a une valeur moyenne (±E-T) de 13,7°C (± 1,4°C). Les lamproies au repos ou cachees ne presentaient une reaction d'evitement a aucun des stimuli experimentaux. [Traduit par la Redaction], Introduction Chemosensory cues are used by prey to assess predation risk (Kats and Dill 1998). Damage-released alarm cues, a type of chemosensory cue, are discharged into an aquatic environment by [...]