Borboletas (Lepidoptera: Papilionoidea e Hesperioidea) da Reserva Biológica do Gurupi, Maranhão, Brasil

Resumo. As borboletas constituem um dos grupos mais utilizados em estudos de monitoramento e mensuração do equilíbrio ambiental, uma vez que são sensíveis a qualquer tipo de alteração ambiental. O objetivo do presente estudo é divulgar a primeira lista de espécies de borboletas da REBIO do Gurupi e estimar a representatividade dessas espécies na comunidade. Foram realizadas coletas bimestrais, durante sete dias consecutivos, entre jan/2010 e jul/2011. Os espécimes foram obtidos com uso de rede entomológica e armadilhas do tipo Van Someren-Rydon. Na análise dos dados foram calculados a frequência das espécies, índices de diversidade, estimativas de riqueza e obteve-se a curva de acúmulo de espécies. Foram obtidos 413 espécimes de 91 espécies, 64 gêneros, 14 subfamílias e seis famílias. A espécie mais frequente foi Morpho menelaus (Linnaeus, 1758). Os índices de diversidades obtidos, quando comparados a outros estudos, são expressivos; a estimativa de espécies e a curva de acúmulo mostram que a comunidade amostrada está subestimada. Com esse trabalho, o Maranhão alcançou 358 espécies de borboletas registradas. Os dados ressaltam a importância da REBIO e das demais Unidades de Conservação para a manutenção da riqueza de borboletas da região. Butterflies (Lepidoptera: Papilionoidea and Hesperioidea) from the Gurupi Biological Reserve, Maranhão State, Brazil Abstract. Butterflies are one of the groups most used in monitoring and measuring environmental balance studies, as they are sensitive to any type of environmental change. The objective of the present study is to disclose the first list of butterfly species of REBIO Gurupi and to estimate the representativeness of these species in the community. Were performed collected quarterly during seven consecutive days, between Jan/2010 and Jul/ 2011. The specimens were obtained using an entomological network and traps of the Van Someren-Rydon type. In the analysis of the data were calculated the frequency of species, diversity indexes, wealth estimates and the curve of species accumulation was obtained. The most frequent species was Morpho menelaus (Linnaeus, 1758). The diversity indexes obtained, when compared to other studies, are expressive; The species estimates and the accumulation curve show that the sampled community is underestimated. With this work, Maranhão reached 358 species of registered butterflies. The data emphasizes the importance of REBIO and other conservation units for the maintenance of the butterflies’ wealth of the region

Impact of abiotic factors and husbandry on saprolegniosis in salmonid farms

Funding Information: This work was financially supported by the EU H2020 [ H2020-SFS-10a-2014 (ParaFishControl, grant agreement No. 634429) (PT, MS, RG, JD-U, PvW, BO & MF)], the BBSRC [ BB/P020224/1 (MS & PvW) & BB/M026566/1 (MS & PvW)] and the University of Aberdeen (MS & PvW). The authors would like to thank all the fish farmers/staff and colleagues who collaborated in the fieldwork and provided valuable information for the study. Publisher Copyright: © 2022 The AuthorsPeer reviewedPublisher PD

Establishing a marine monitoring programme to assess antibiotic resistance: a case study from the Gulf Cooperation Council (GCC) region

The World Health Organization considers antimicrobial resistance as one of the most pressing global issues which poses a fundamental threat to human health, development, and security. Due to demographic and environmental factors, the marine environment of the Gulf Cooperation Council (GCC) region may be particularly susceptible to the threat of antimicrobial resistance. However, there is currently little information on the presence of AMR in the GCC marine environment to inform the design of appropriate targeted surveillance activities. The objective of this study was to develop, implement and conduct a rapid regional baseline monitoring survey of the presence of AMR in the GCC marine environment, through the analysis of seawater collected from high-risk areas across four GCC states: (Bahrain, Oman, Kuwait, and the United Arab Emirates). 560 Escherichia coli strains were analysed as part of this monitoring programme between December 2018 and May 2019. Multi-drug resistance (resistance to three or more structural classes of antimicrobials) was observed in 32.5% of tested isolates. High levels of reduced susceptibility to ampicillin (29.6%), nalidixic acid (27.9%), tetracycline (27.5%), sulfamethoxazole (22.5%) and trimethoprim (22.5%) were observed. Reduced susceptibility to the high priority critically important antimicrobials: azithromycin (9.3%), ceftazidime (12.7%), cefotaxime (12.7%), ciprofloxacin (44.6%), gentamicin (2.7%) and tigecycline (0.5%), was also noted. A subset of 173 isolates was whole genome sequenced, and high carriage rates of qnrS1 (60/173) and bla CTX-M-15 (45/173) were observed, correlating with reduced susceptibility to the fluoroquinolones and third generation cephalosporins, respectively. This study is important because of the resistance patterns observed, the demonstrated utility in applying genomic-based approaches to routine microbiological monitoring, and the overall establishment of a transnational AMR surveillance framework focussed on coastal and marine environments

Indirect interactions between prey : modeling and influence of the behavior of a common predator

Cette thèse a pour objet la modélisation de systèmes multi-proies–prédateurs. Elle s’intéresse particulièrement à l’influence du comportement d’un prédateur sur les interactions indirectes entre ses proies, i.e. l’effet de l’ajout d’une proie sur la densité des autres. La théorie classique prédit l’occurrence d’effets indirects négatifs entre les proies, ou compétition apparente, résultant de l’interaction avec un prédateur commun ; des résultats plus récents identifient certains mécanismes à même d’atténuer ces effets négatifs. Nos travaux revisitent les hypothèses autour de ces mécanismes dans des systèmes composés de deux proies et de leur prédateur commun. Après avoir fixé le cadre écologique en rappelant les principaux types d’interactions directes et indirectes, nous introduisons les modèles proies-prédateurs classiques. Les travaux se concentrent ensuite sur une famille de modèles présentant de la densité-dépendance négative chez les prédateurs couplés à différentes modélisations du comportement des prédateurs lorsqu’ils sont confrontés à plusieurs types de proies. Nous montrons notamment que les interactions entre ces mécanismes peuvent inverser la compétition apparente et, contre intuitivement, accroître la densité des proies par l’intermédiaire d’un prédateur commun. Nos résultats trouvent pour partie application en lutte biologique, où il est courant de chercher à favoriser les auxiliaires en aménageant leur environnement (apport de nourriture alternative, refuge, ...). Ils suggèrent que de telles pratiques peuvent se révéler contre-productives, le contrôle des ravageurs pouvant être affaibli du fait d’une distraction de leurs prédateurs.This thesis deals with multi-prey–predators modeling. It is particularly focused on the influence of the behavior of a predator on indirect interactions between its prey, i.e, the effect of the addition of a prey on the other prey. Classical theory predicts the occurrence of negative indirect effects between prey, or apparent competition, resulting from the interaction with a common predator. More recent results identify mechanisms that mitigate these negative effects. Our work revisits the assumptions about these mechanisms in systems composed of two prey and their common predator. After setting the ecological framework by recalling the main types of direct and indirect interactions, we introduce classical predator-prey models. The work then focuses on a family of models with predator negative density-dependence coupled with different models of predator behavior when faced with different types of prey. We show that the interactions between these mechanisms can reverse apparent competition and counter-intuitively, increase prey density through their common predator. Our results are relevant to biological control programs, where a common practice aims at fostering biological control agents by providing them with alternative food or shelters. Our theory suggests that such practices may be counter-productive, pest control being disrupted by a predator distraction effect

Des interactions indirectes entre les proies : modélisation et influence du comportement du prédateur commun

This thesis deals with multi-prey–predators modeling. It is particularly focused on the influence of the behavior of a predator on indirect interactions between its prey, i.e, the effect of the addition of a prey on the other prey. Classical theory predicts the occurrence of negative indirect effects between prey, or apparent competition, resulting from the interaction with a common predator. More recent results identify mechanisms that mitigate these negative effects. Our work revisits the assumptions about these mechanisms in systems composed of two prey and their common predator. After setting the ecological framework by recalling the main types of direct and indirect interactions, we introduce classical predator-prey models. The work then focuses on a family of models with predator negative density-dependence coupled with different models of predator behavior when faced with different types of prey. We show that the interactions between these mechanisms can reverse apparent competition and counter-intuitively, increase prey density through their common predator. Our results are relevant to biological control programs, where a common practice aims at fostering biological control agents by providing them with alternative food or shelters. Our theory suggests that such practices may be counter-productive, pest control being disrupted by a predator distraction effect.Cette thèse a pour objet la modélisation de systèmes multi-proies–prédateurs. Elle s’intéresse particulièrement à l’influence du comportement d’un prédateur sur les interactions indirectes entre ses proies, i.e. l’effet de l’ajout d’une proie sur la densité des autres. La théorie classique prédit l’occurrence d’effets indirects négatifs entre les proies, ou compétition apparente, résultant de l’interaction avec un prédateur commun ; des résultats plus récents identifient certains mécanismes à même d’atténuer ces effets négatifs. Nos travaux revisitent les hypothèses autour de ces mécanismes dans des systèmes composés de deux proies et de leur prédateur commun. Après avoir fixé le cadre écologique en rappelant les principaux types d’interactions directes et indirectes, nous introduisons les modèles proies-prédateurs classiques. Les travaux se concentrent ensuite sur une famille de modèles présentant de la densité-dépendance négative chez les prédateurs couplés à différentes modélisations du comportement des prédateurs lorsqu’ils sont confrontés à plusieurs types de proies. Nous montrons notamment que les interactions entre ces mécanismes peuvent inverser la compétition apparente et, contre intuitivement, accroître la densité des proies par l’intermédiaire d’un prédateur commun. Nos résultats trouvent pour partie application en lutte biologique, où il est courant de chercher à favoriser les auxiliaires en aménageant leur environnement (apport de nourriture alternative, refuge, ...). Ils suggèrent que de telles pratiques peuvent se révéler contre-productives, le contrôle des ravageurs pouvant être affaibli du fait d’une distraction de leurs prédateurs

Optimal foraging predators in Leslie Gower models with alternative prey

International audienceOptimal foraging theory defines the diet choice of a predator by imposing that it chooses the prey that is instantaneously the most beneficial for him [1]. It has been shown that this phenomenon leads to a switching diet and to the persistence of both prey and predators in generalized Lokta-Volterra models [2, 3]. This framework can be useful to study the influence of an introduced alternative prey on a one-prey-one-predator system. In a Lokta-Volterra model, this introduction can enhance predator growth and have negative effects on the main prey, which is called apparent competition [4]. In this work, we focus on a Leslie-Gower model with two dynamic prey, where the preyed population determines the carrying capacity of the predator population. Optimal foraging aiming at the maximization of the per capita growth rate of the predator population then leads to the maximization of its instantaneous carrying capacity. This optimization defines two main regions in the population state space, separated by a dividing plane, and thus three diet strategies. The predator population will have the choice between eating only the main prey, or only the alternative prey, or following a mixed diet. In each of these three regions, the dynamics which are relevant to the predator reduce to a Leslie-Gower model with a stable positive equilibrium. Depending on the parameters of the system, different global behaviors arise. However, in all cases, there is only a single positive stable equilibrium, which can potentially lie on the dividing plane; the equilibrium is such that its predator population is larger or equal than that in the absence of the alternative prey. Also, the presence of an alternative prey is never detrimental to the main prey; so the apparent competition does not hold

Des interactions indirectes entre les proies (modélisation et influence du comportement du prédateur commun)

Cette thèse a pour objet la modélisation de systèmes multi-proies prédateurs. Elle s intéresse particulièrement à l influence du comportement d un prédateur sur les interactions indirectes entre ses proies, i.e. l effet de l ajout d une proie sur la densité des autres. La théorie classique prédit l occurrence d effets indirects négatifs entre les proies, ou compétition apparente, résultant de l interaction avec un prédateur commun ; des résultats plus récents identifient certains mécanismes à même d atténuer ces effets négatifs. Nos travaux revisitent les hypothèses autour de ces mécanismes dans des systèmes composés de deux proies et de leur prédateur commun. Après avoir fixé le cadre écologique en rappelant les principaux types d interactions directes et indirectes, nous introduisons les modèles proies-prédateurs classiques. Les travaux se concentrent ensuite sur une famille de modèles présentant de la densité-dépendance négative chez les prédateurs couplés à différentes modélisations du comportement des prédateurs lorsqu ils sont confrontés à plusieurs types de proies. Nous montrons notamment que les interactions entre ces mécanismes peuvent inverser la compétition apparente et, contre intuitivement, accroître la densité des proies par l intermédiaire d un prédateur commun. Nos résultats trouvent pour partie application en lutte biologique, où il est courant de chercher à favoriser les auxiliaires en aménageant leur environnement (apport de nourriture alternative, refuge, ...). Ils suggèrent que de telles pratiques peuvent se révéler contre-productives, le contrôle des ravageurs pouvant être affaibli du fait d une distraction de leurs prédateurs.This thesis deals with multi-prey predators modeling. It is particularly focused on the influence of the behavior of a predator on indirect interactions between its prey, i.e, the effect of the addition of a prey on the other prey. Classical theory predicts the occurrence of negative indirect effects between prey, or apparent competition, resulting from the interaction with a common predator. More recent results identify mechanisms that mitigate these negative effects. Our work revisits the assumptions about these mechanisms in systems composed of two prey and their common predator. After setting the ecological framework by recalling the main types of direct and indirect interactions, we introduce classical predator-prey models. The work then focuses on a family of models with predator negative density-dependence coupled with different models of predator behavior when faced with different types of prey. We show that the interactions between these mechanisms can reverse apparent competition and counter-intuitively, increase prey density through their common predator. Our results are relevant to biological control programs, where a common practice aims at fostering biological control agents by providing them with alternative food or shelters. Our theory suggests that such practices may be counter-productive, pest control being disrupted by a predator distraction effect.NICE-Bibliotheque electronique (060889901) / SudocSudocFranceF

Optimal foraging predators in Leslie Gower models with alternative prey

International audienceOptimal foraging theory defines the diet choice of a predator by imposing that it chooses the prey that is instantaneously the most beneficial for him [1]. It has been shown that this phenomenon leads to a switching diet and to the persistence of both prey and predators in generalized Lokta-Volterra models [2, 3]. This framework can be useful to study the influence of an introduced alternative prey on a one-prey-one-predator system. In a Lokta-Volterra model, this introduction can enhance predator growth and have negative effects on the main prey, which is called apparent competition [4]. In this work, we focus on a Leslie-Gower model with two dynamic prey, where the preyed population determines the carrying capacity of the predator population. Optimal foraging aiming at the maximization of the per capita growth rate of the predator population then leads to the maximization of its instantaneous carrying capacity. This optimization defines two main regions in the population state space, separated by a dividing plane, and thus three diet strategies. The predator population will have the choice between eating only the main prey, or only the alternative prey, or following a mixed diet. In each of these three regions, the dynamics which are relevant to the predator reduce to a Leslie-Gower model with a stable positive equilibrium. Depending on the parameters of the system, different global behaviors arise. However, in all cases, there is only a single positive stable equilibrium, which can potentially lie on the dividing plane; the equilibrium is such that its predator population is larger or equal than that in the absence of the alternative prey. Also, the presence of an alternative prey is never detrimental to the main prey; so the apparent competition does not hold

Evaluating differences in marine spatial data resolution and robustness:A North Sea case study

Seabed substrates have the capacity to support a variety of marine communities. However, habitats provided by natural substrates are increasingly modified and supplemented by man-made structures. These provide hard surfaces suitable for colonisation by sedentary and/or non-migratory organisms, and may contribute to an interconnected system of benefit to diverse marine populations. Robust assessment of the influence of such structures is, therefore, a necessary consideration for their long-term management. The challenge of compiling and manipulating data for input to two North Sea models is described. Source data were processed and gridded at three different spatial resolutions to investigate the effect of scale on spatial relationships. Choice of grid size was found to exacerbate existing uncertainty in location and extent of features, influencing interpretation of their spatial distributions at the different scales examined. The small spatial footprint of man-made structures, compared with natural substrates, may lead to underestimation of the influence of the former at coarser model scales. Choices must be made between data availability, spatial resolution and accuracy, modelling and analysis requirements, to identify robust approaches to reliable outcomes. Model sensitivity and uncertainty analyses are recommended for application in data-limited situations. Greater openness and cooperation in data-sharing is required for robust scientific modelling to underpin decision-making in the marine environment

Efficacy testing of an immersion vaccine against Aeromonas salmonicida and immunocompetence in ballan wrasse (Labrus bergylta, Ascanius)

The development of effective vaccines is a critical step towards the domestication of emerging fish species for aquaculture. However, traditional vaccine delivery through intraperitoneal (i.p.) injection requires fish to reach a minimum size and age and therefore cannot provide protection at early developmental stages when infection may occur. This study investigated the effectiveness of immersion vaccination with respect to immunocompetence in a cleaner fish species (ballan wrasse, Labrus bergylta, Ascanius) used in Atlantic salmon farming as an alternative means to control sea lice. The species is susceptible to atypical strains of Aeromonas salmonicida (aAs) at early life stages (80 dph, MHC II and IgM transcripts were first reported at 35 and 75 dph, respectively, suggesting a window of immunocompetence. The results provide important new information on the onset of adaptive immunity in ballan wrasse and highlight that immersion vaccination in the species for protection against aAs should be performed at later developmental stages (>1.5 g) in the hatchery