Spelling suggestions: "subject:"haemulidae"" "subject:"haemulide""
1 |
Impactos do turismo na dieta de Haemulon aurolineatum (Cuvier, 1830) em recifes coralíneos do Rio Grande do NorteSilva, Fernanda Carolina da 26 February 2018 (has links)
Submitted by Eunice Novais (enovais@uepg.br) on 2018-09-06T18:06:00Z
No. of bitstreams: 2
license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5)
Fernanda Silva.pdf: 8612783 bytes, checksum: 75134e09c730581d4c96c8bf2b470456 (MD5) / Made available in DSpace on 2018-09-06T18:06:00Z (GMT). No. of bitstreams: 2
license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5)
Fernanda Silva.pdf: 8612783 bytes, checksum: 75134e09c730581d4c96c8bf2b470456 (MD5)
Previous issue date: 2018-02-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O turismo em ambientes marinhos é uma atividade crescente a cada ano, principalmente em regiões de litoral atrativo. Uma das principais práticas dos turistas refere-se à oferta de alimentação suplementar para peixes, tais como pão, biscoitos e outros alimentos artificiais na dieta desses indivíduos. Por um lado, essa atividade pode ajudar na sensibilização ambiental, mas também resulta em impactos negativos pouco compreendidos. Sendo assim, o objetivo deste estudo foi analisar os efeitos da alimentação por turistas na dieta do peixe Haemulon aurolineatum em recifes coralíneos do Rio Grande do Norte. Duas áreas foram escolhidas para a coleta dos espécimes: uma com alimentação suplementar ofertada por turistas – Parrachos de Maracajaú, e outra com alimentação natural – Parrachos de Rio do Fogo. Foram tomadas as medidas de comprimento, peso, índice hepatossomático (IHS) e fator de condição (K) das duas áreas amostrais. Para confirmação da classe etária dos indivíduos, foram contados os anéis de crescimento presentes no otólito Sagitta. Os itens consumidos foram identificados na menor categoria taxonômica possível e os resultados foram comparados através de NMDS e ANOSIM. Também foi analisado o teor de amido do conteúdo estomacal. O teste estatístico t apontou diferença para o comprimento dos indivíduos, possivelmente pela alta ingestão de alimentos. Entretanto os testes apontaram equivalência para o peso, IHS e K. A análise de NMDS diferenciou os itens consumidos para as duas regiões amostradas e a análise de similaridade confirmou que o turismo reflete em modificações na composição da dieta. O conteúdo estomacal dos indivíduos coletados na região com alimentação suplementar apresentou 48,73% de amido em sua composição. Considerando a dieta natural dessa espécie, a ingestão de carboidratos pode interferir no acúmulo energético individual. Adicionalmente, as presas habituais de H. aurolineatum não estão sendo capturadas, o que pode acarretar desequilíbrio entre as populações. Nossos resultados procuram contribuir para o manejo de áreas recifais, com redução do volume e controle do tipo de alimento ofertado, para que o turismo seja de fato, uma atividade sustentável. / Tourism in marine environments is growing every year, especially in attractive coastal regions. One of the regular practices of tourists refers to supplementary food provisioning for fish, such as bread, biscuits and other artificial foods in the diet of these individuals. On the one hand, this activity can assist in fish conservation and environmental awareness, but on the other hand it results in negative impacts little understood so far. Thus, the objective of this study was to analyze the effects of food offer by tourists in the diet of the fish Haemulon aurolineatum in coral reefs of Rio Grande do Norte. Two areas were chosen for collection: one with supplementary feeding offered by tourists - Parrachos de Maracajau, and another with natural food - Parrachos do Rio do Fogo. Measures of length, weight, hepatosomatic index (HSI) and condition factor (K) of the two sampling areas were taken. To confirm the age class of individuals, the growth rings present in the otolith Sagitta were counted. The consumed items were identified to the smallest taxonomic category possible and the results were compared through NMDS and ANOSIM. The starch content of the stomach contents has also been analyzed. The t test pointed out differences in individuals’ length, possibly due to high food intake. However, the t tests pointed equivalent weight, HSI and K for both areas. The NMDS differentiated the items consumed for the two sampled regions and the analysis of similarity confirmed that tourism reflects on modifications in diet composition. The stomach contents of supplementary fed individuals presented 48.73% starch in its composition. Considering the natural diet of this species, carbohydrate intake can interfere with individual energy accumulation. Additionally, H. aurolineatum habitual preys are not being captured, which may lead to imbalance among the populations. Our results try to contribute to the management of reef areas, with a reduction in the volume and control of the food type being offered, so that tourism can become in fact a sustainable activity.
|
2 |
The Influence of Habitat Quality on the Community Structure, Distribution Pattern, Condition, and Growth of Coral Reef Fish: A Case Study of Grunts (Haemulidae) from Antigua B.W.I, A Small Island SystemConstantine, Sherry Lynette 25 July 2008 (has links)
The goal of this research was to determine the relative quality of near shore marine areas by investigating their influence on Haemulidae community structure, distribution pattern, condition, and growth. Habitat was defined at the small spatial scale of individual habitat types such as seagrass beds, mangroves and coral reefs, and at the broader spatial scale of the interconnection of these individual habitat types within a mosaic (IHM). Ten spatial, biotic and abiotic parameters (percentage coverage of sand, mangroves, hard substrate, and seagrass, turbidity, pH, salinity, temperature, average depth, and predator density) were investigated. These environmental characteristics acted as proxies for the quality of IHMs. The major findings of the research were: (1) IHMs and discrete habitat types in tropical marine systems are not always equal in quality. Further, the highest quality IHMs/discrete habitat types have the critical resources whether spatial, abiotic or biotic, at the optimum levels needed by organisms to carry out their critical life functions; (2) IHMs of the highest quality contain all the discrete habitat types needed by organisms to carry out their life processes in a spatial arrangement that maximizes energy savings; (3) IHMs can be of high quality in the absence of one habitat type, if this habitat type is replaced by another that can take on its ecological role; and (4) the percentage cover of hard substratum and seagrass, temperature, and predator density have a big impact on Haemulidae distribution pattern, community structure, condition and growth. In addition, this research highlighted some of many characteristics of benthic habitats such as type and configuration that should be included in the design of Marine Protected Areas for the effective management of fisheries resources. Effective Marine Protected Areas should have (1) large overall area with benthic habitat types of high quality; (2) spatial configurations with short distances (corridors) between habitat types; (3) spatial arrangements that place all individual habitat types in connection with all other habitat types so that energy expenditure in moving among habitat types is reduced; (4) habitats with high structural complexity; and (5) the inclusion of all the habitat types needed by focal organisms to carry out their life processes, or surrogate habitat types that can take on the role of ones that are absent.
|
3 |
Revisão taxonômica das espécies brasileiras do gênero Pomadasys Lacépède, 1802 (Teleostei : Haemulidae)Bandeira, Wagner Desidério 10 June 2002 (has links)
Submitted by Alberto Vieira (martins_vieira@ibest.com.br) on 2018-01-12T17:10:42Z
No. of bitstreams: 1
566964.pdf: 7932354 bytes, checksum: 40e069b413090587a6fd2cca87f41692 (MD5) / Made available in DSpace on 2018-01-12T17:10:43Z (GMT). No. of bitstreams: 1
566964.pdf: 7932354 bytes, checksum: 40e069b413090587a6fd2cca87f41692 (MD5)
Previous issue date: 2002-06-10 / A taxonomia das espécies do gênero Pomadasys Lacépède que ocorrem no Brasil é revista. Das 12 espécies do gênero, ou de seus sinônimos, citadas para o Brasil, apenas as ocorrências de Pomadasys corvinaeformis (Steindachner, 1868) e P. ramosum (Poey, 1860) foram confirmadas com base em material examinado. Uma terceira espécie, identificada tradicionalmente como P. crocro (Cuvier, 1830), revelou-se distinta desta espécie do Mar do Caribe e é aqui reconhecida como nova. A análise do material-tipo de P. crocro da Ilha da Martinica, de exemplares de uma forma similar do Panamá e do material da espécie nova brasileira, sugere tratar-se o grupo crocro de um complexo de espécies alopátricas muito próximas morfologicamente. Problemas relativos a possíveis grupos de espécies em Pomadasys são comentados. Para cada uma das espécies reconhecidas do Brasil são dadas: uma diagnose, descrição, distribuição geográfica com base em material examinado, e dados bio-ecológicos disponíveis. Uma chave de identificação para as espécies brasileiras de Pomadasys é incluída. / The taxonomy of the species of Pomadasys Lacépède from the coast of Brazil is reviewed. Of the 12 species of the genus, or of its synonyms recorded from Brazil, only Pomadasys corvinaeformis (Steindachner, 1868) and P. ramosum (Poey, 1860) were confirmed based on examined material. A third species, traditionally misidentified as P. crocro (Cuvier, 1830), revealed itself distinct from this species of the Caribbean Sea and is herein recognized as new. The study of the type material of P. crocro from Martinica, of specimens from a closely similar form from Panama, and the material of the Brazilian new species suggests that crocro may represent a species-group of allopatric and closely similar species. Problems related to, the existence of species-groups within Pomadasys are discussed. A diagnosis, a brief description, the geographic distribution based on examined specimens, and available information on species bioecology are given for each of the species recognized from Brazil. A key for the identification of the Brazilian species of Pomadasys is given.
|
4 |
Haemulidae, modelo cariot?pico de estase evolutivaMotta Neto, Cl?vis Coutinho da 26 November 2011 (has links)
Made available in DSpace on 2014-12-17T14:02:01Z (GMT). No. of bitstreams: 1
ClovisCMN_DISSERT.pdf: 5818317 bytes, checksum: 71340e95f66a43118e689e2a248f3dd3 (MD5)
Previous issue date: 2011-11-26 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Os perciformes constituem o maior e mais diversificado grupo de peixes. Uma parcela consider?vel de suas esp?cies apresenta um marcante conservadorismo cromoss?mico exibindo um padr?o caracterizado por 2n=48a, NF=48, que tem sido apontado como uma condi??o basal para a Ordem. Blocos heterocrom?ticos reduzidos e RONs simples s?o caracter?sticos para este grupo de peixes. No entanto, n?o se encontra ainda bem estabelecido se este conservadorismo se deve, em parte, a dados provenientes de bandamentos cromoss?micos pouco resolutivos, como os convencionalmente utilizados nas caracteriza??es citogen?ticas das esp?cies marinhas ou a uma condi??o peculiar cariot?pica deste grupo. Visando clarificar os processos envolvidos no peculiar conservadorismo cromoss?mico observado nesta Ordem, cinco esp?cies da fam?lia Haemulidae foram submetidas ? variadas t?cnicas citogen?ticas como colora??o com Giemsa, bandamento C e impregna??o por nitrato de prata, bem como digest?o com enzimas de restri??o (AluI, TaqI, PstI e EcoRI), bandamento de replica??o pela incorpora??o do an?logo de base 5 BrdU, colora??o com os fluorocromos CMA3/MM e DAPI, double FISH com sondas para as subunidades ribossomais 5S e 45S, sendo tamb?m analisadas morfometricamente atrav?s de morfometria geom?trica (MG). Os dados obtidos permitiram identificar um alto grau de similaridade cariot?pica neste grupo independente do n?vel de resolu??o das t?cnicas utilizadas. As esp?cies Conodon nobilis, Pomadasys corvinaeformis, Haemulon aurolineatum, H. plumierii e H. steindachneri apresentaram uma macroestrutura cariot?pica comum composta por 2n=48a (NF=48), com RONs simples localizadas em um mesmo par cromoss?mico (24? par) nas esp?cies C. nobilis, H. aurolineatum H. plumierii e H. steindachneri e em outro par em P. corvinaeformis (18? par), considerando-se estas regi?es caracteres citotaxon?micos pouco importantes. O padr?o heterocrom?tico apresentou-se similar para todas as esp?cies, observando-se reduzidos blocos heterocrom?ticos detectados preferencialmente em regi?o centrom?ricas e em menor n?mero em regi?es pericentrom?ricas e telom?ricas. Contrastando com a reduzida diferencia??o cromoss?mica observada, as an?lises por MG indicaram uma consp?cua diferencia??o morfol?gica entre as esp?cies. Condi??es ambientais com reduzidas barreiras biogeogr?ficas, caracter?sticas biol?gicas, decorrente da presen?a de grandes contingentes populacionais uniformemente distribu?dos em largas ?reas costeiras, que promoveriam a manuten??o do fluxo g?nico dentro das popula??es, associadas ?s caracter?sticas cariot?picas peculiares, poderiam desempenhar uma a??o sin?rgica contribuindo para a evolu??o bradit?lica do cari?tipo nas esp?cies de Haemulidae
|
5 |
Biologia reprodutiva do mercador, Anisotremus virginicus (Linnaeus, 1758), capturado no litoral Norte do Estado de PernambucoBATISTA, Carlos Hudson de Oliveira 10 December 2012 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2017-02-09T11:30:33Z
No. of bitstreams: 1
Carlos Hudson de Oliveira Batista.pdf: 759611 bytes, checksum: 1d4523c0cea26587e0787d1790fb0c2f (MD5) / Made available in DSpace on 2017-02-09T11:30:33Z (GMT). No. of bitstreams: 1
Carlos Hudson de Oliveira Batista.pdf: 759611 bytes, checksum: 1d4523c0cea26587e0787d1790fb0c2f (MD5)
Previous issue date: 2012-12-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Species from the Haemulide family are amongst the most abundant fishes on coral reefs, representing an important component of the artisanal fisheries in the northest coast of Pernambuco State. Nevertheless, the biology of several species is poorly known, and so the present work aims at generating information on the reproductive biology (sex ratio, size at maturity, spawning season and fecundity) of Anisotremus virginicus. A total of 449 specimens were analyzed, 230 (51.2%) male and 219 (48.8%)female, resulting in a sex ratio of 1.05 males to 1 female. The fork length ranged from 12.1 to 28.0 cm (mean ± S.E. 19,4 ± 0.2 cm FL) in males, whereas the total weight (TW) ranged from 55.65 to 512.50 g (mean ± S.E. 197.88 ± 5.1). Females length ranged from 11.6 to 28.0 cm FL (mean ± S.E. 19.3 ± 0.1) and weight ranged from 40.63 to 451.0 (mean ± S.E. 198.6 ± 4.6). Length-weight relationships between sex were not significantly different (Mann-Whitney U-test, nmale = 230, nfemale = 219, P>0.05). Size at first maturity was estimated at 17.9 and 17.8 cm FL for females and males, respectively. Spawning activity was observed all year-round, but A. virginicus presented a higher reproduction activity from October to February (spring and summer). Fecundity (F)ranged from 20.496 to 338.803 oocytes, with a mean of 123.348 eggs/gonad. The oocyte development was asynchronous and characterized by the presence of all stages of oocytes development. / As espécies da família Haemulidae estão entre as mais abundantes nos ambientes de recifes, representando um componente importante da pesca artesanal praticado no litoral norte do estado de Pernambuco. Apesar disso, a biologia das diversas espécies não é bem compreendida, de modo que o presente estudo objetiva gerar informações sobre a biologia reprodutiva (proporção sexual, tamanho de primeira maturidade (L50), período de desova e fecundidade) de Anisotremus virginicus. Um total de 449 espécimes foi analisado, 230 (51,2%) machos e 219 (48,8%) fêmeas, apresentando uma proporção sexual de 1,05 machos: 1 fêmea. O comprimento furcal (CF) dos machos variou de 12,1 a 28,0 cm (média ± E.P. 19,4 ± 0,2 cm CF) e peso total (PT) entre 55,6 a 512,5 g (média ± E.P. 197,88 ± 5,1). Para as fêmeas o comprimento variou de 11,6 a 28,0 cm CF (média ± E.P. 19,3 ± 0,1) e peso entre 40,63 a 451,0 (média ± E.P. 198,6 ± 4,6). Diferenças estatísticas não foram observadas para as relações de peso e comprimento entre os sexos (Mann-Whitney U-test, nmachos = 230, nfêmeas = 219, P<0,05). Os dados analisados sugerem que o tamanho de primeira maturação (L50) para as fêmeas e machos é de 16,7 e 17,1 cm de comprimento furcal (CF) respectivamente, o que corresponde a 59% do comprimento máximo observado no presente estudo. O período de desova foi sugerido para os meses de fevereiro-abril e outubro, final da primavera e final do verão, com desovas menores ao longo do ano. A fecundidade variou entre 20.496,0 a 338.803,0 ovócitos, com média de 123.348,0 ovócitos/gônada. Foi observado um desenvolvimento assincrônico dos ovócitos, caracterizado pela presença de todos os estágios de desenvolvimento ovocitário.
|
6 |
Helmintofauna monogenética e as táticas reprodutivas da biquara Haemulon plumierii (Lacepède, 1802) / Helmintofauna monogenétic and the reproductive tactics of white grunt Haemulon plumierii (Lacepède, 1802)Fernandes, Bruna Laura de França 21 February 2017 (has links)
Submitted by Socorro Pontes (socorrop@ufersa.edu.br) on 2017-06-29T12:11:05Z
No. of bitstreams: 1
BrunaLFF_DISSERT.pdf: 1489360 bytes, checksum: b80c12e94b27433d39f8e4d7c7b1d47e (MD5) / Made available in DSpace on 2017-06-29T12:11:06Z (GMT). No. of bitstreams: 1
BrunaLFF_DISSERT.pdf: 1489360 bytes, checksum: b80c12e94b27433d39f8e4d7c7b1d47e (MD5)
Previous issue date: 2017-02-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Haemulon plumierii are coastal fish that inhabit waters from the Chesapeake Bay - US, Gulf of Mexico, Caribbean and the entire coast of Brazil. Fish are the aquatic vertebrates that have the highest rates of parasitism and use different reproductive tactics in their life strategy to maximize reproduction and ensure the survival of their offspring to adulthood. The present work verified whether the ectoparasitism by monogenetic can influence the reproductive tactics of H. plumierii in marine waters in the North Atlantic Ocean Southwest (4º 50'57 ''S and 37º51'36''O), near the Rio Grande do Norte / Brazil, for that, the parasitic research of monogenetic was carried out and the study of the reproductive tactics of H. Plumierii. 240 copies were captured of H. plumierii hosts in the period from august 2015 to july 2016, with amplitudes of total weight between 84.5 to 517.5g and total length of 175 to 315mm. Monogenetics parasitized 106 H. plumierii fish among 240 examined, and 162 parasites were collected that were distributed in two subclasses: Monopisthocotylea and Polyopisthocotylea. Monopisthocotylea of the family Capsalidae in the genus Encotyllabe (75 in the gills and 9 in the skin) and Entobdella (1 in the gills and 17 in the skin); Polyopisthocotylea in the family Diclidophoridae in the genus Choricotyle (51 in the gills and 9 in the skin). H. plumierii was identified as a new host for the monogenéticos Encotyllabe sp., Entobdella hipoglossi, and Choricotyle sp., being the first record of the genus Entobdella in the family Haemulidae. The monogenetic parasites had a higher parasite preference for the gills, presenting low parasitic ecological indices. It was determined that H. plumierii are seasonal strategist fish in which males present greater total weight, total length and number in relation to females, however, there were no significant differences. It was recorded that the H. plumierii species has the following reproductive tactics: growth of the negative allometric type indicating a greater body increase in length than in weight; independent of this immature (young) stage it was verified macroscopically that adults have three stages of gonadal development (in maturation, mature and emptied) during the reproductive cycle; this animal altered its reproductive strategy, initiating reproductive development with precocity where the absolute fecundity was 52,123 oocytes with a synchronous spawning type in more than two groups; the reproductive period is comprised throughout the year with the highest occurrence in two moments in the months of march to june and the second of august to October. The present work reported that the species Haemulon plumierii is parasitized by monogenetic Monopisthocotylea and Polyopisthocotylea with low prevalence rates, medium intensity and average abundance, and that H. plumierii is a seasonal strategist where his reproductive tactics were not influenced by the parasitism of monogenetics in conditions of low parasitic ecological indices / Haemulon plumierii são peixes costeiros que habitam águas desde a Baía de Chesapeake - EUA, Golfo do México, Caribe e toda a costa do Brasil. Os peixes são os vertebrados aquáticos que apresentam os maiores índices de parasitismo e usam diferentes táticas reprodutivas em sua estratégia de vida para maximizar a reprodução e garantir a sobrevivência dos seus descendentes até a idade adulta. O presente trabalho verificou se o ectoparasitismo por monogenéticos pode influenciar as táticas reprodutivas de H. plumierii nas águas marinhas no Norte do Oceano Atlântico Sudoeste (4º 50’57’’S e 37º51’36’’O), próximo ao Rio Grande do Norte/Brasil, para isso, realizou-se a pesquisa parasitária de monogenéticos e o estudo das táticas reprodutivas de H. plumierii. Foram capturados 240 exemplares de hospedeiros H. plumierii no período de agosto de 2015 a julho de 2016, com amplitudes de peso total entre 84,5 a 517,5g e comprimento total de 175 a 315mm. Os Monogenéticos parasitaram 106 peixes H. plumierii entre 240 examinados, sendo coletados 162 parasitos que estavam distribuídos em duas subclasses: Monopisthocotylea e Polyopisthocotylea. Monopisthocotylea da família Capsalidae nos gêneros Encotyllabe (75 nas brânquias e 9 no tegumento) e Entobdella (1 nas brânquias e 17 no tegumento); Polyopisthocotylea na família Diclidophoridae no gênero Choricotyle (51 nas brânquias e 9 no tegumento). H. plumierii foi identificado como um novo hospedeiro para os monogenéticos Encotyllabe sp., Entobdella hipoglossi, e Choricotyle sp., sendo o primeiro registro do gênero Entobdella na família Haemulidae. Os parasitos monogenéticos apresentaram uma maior preferência parasitária pelas brânquias, apresentando baixos índices ecológicos parasitários. Determinou-se que H. plumierii são peixes estrategistas sazonais no qual os machos apresentam maior peso total, comprimento total e número em relação as fêmeas, contudo não ocorreram diferenças significativas. Registrou-se que a espécie H. plumierii possui as seguintes táticas reprodutivas: crescimento do tipo alométrico negativo indicando um incremento corporal maior em comprimento do que em peso; independente deste estádio imaturo (jovens) foi verificado macroscopicamente que os adultos possuem três estádios de desenvolvimento gonadal (em maturação, maduro e esvaziado) durante o ciclo reprodutivo; este animal alterou sua estratégia reprodutiva iniciando o desenvolvimento reprodutivo com precocidade onde a fecundidade absoluta foi de 52.123 ovócitos com um tipo de desova sincrônico em mais de dois grupos; o período reprodutivo está compreendido durante todo o ano com maior ocorrência em dois momentos nos meses de março a junho e o segundo de agosto a outubro. O presente trabalho registrou que a espécie Haemulon plumierii é parasitado por monogenéticos Monopisthocotylea e Polyopisthocotylea com baixos índices de prevalência, intensidade média e abundância média, e que H. plumierii é um estrategista sazonal onde suas táticas reprodutivas não sofreram influência pelo parasitismo de monogenéticos nas condições de baixos índices ecológicos parasitários / 2017-06-29
|
7 |
Multi-Experimental Examination of Haemulon Species (Haemulidae) Early-Life Ecology on Southeast Mainland Florida Coral ReefsJordan, Lance K. B. 01 January 2010 (has links)
Grunts (Haemulidae: Percoidei) represent one of the most abundant and speciose families on western North Atlantic coral reefs including 15 diverse species from the genus Haemulon. For this dissertation focusing on Haemulon, three studies were conducted to examine 1) spatio-temporal distributions of early-life stage (newly settled and early juvenile) individuals throughout the southeast mainland Florida reefscape, 2) species-specific, depth-variable distributional patterns of newly settled individuals and the potential influence of predation on the observed patterns, and 3) the effects of burying nearshore hardbottom settlement habitat and the efficacy of mitigating for the lost habitat using limestone boulder reefs. The combined results of the studies suggest that newly settled Haemulon spp. utilize shallow reef habitats (highest densities on nearshore hardbottom) with peak abundances in summer months. While newly settled individuals were never observed on natural reef habitats below 12 m depth, studies using artificial reefs (ARs) showed that new settlers were commonly recorded at depths of 21 m. Species-specific patterns of new settler depth utilization were found when replicate ARs at three sites (8 m, 12 m, and 21 m depth) were examined. Of the three most abundant species collected during fortnightly sampling of ARs, newly settled H. flavolineatum and H. aurolineatum were found at all three sites while H. striatum was found almost exclusively at the 21-m site. Comparison of caged and noncaged ARs allowed for inferences to be made regarding depth-variable predation pressure on newly settled Haemulon spp. Results (based on delta density differences between caged and noncaged ARs at each site) suggest lower predation pressure at the 8-m site, relative to the 12-m and 21-m sites. Depth-variable predation pressure may, in part, explain the distributional patterns exhibited by newly settled Haemulon spp. on the natural reef. I examined annual change in early-stage Haemulon spp. populations on nearshore hardbottom (NHB) to assess the impact of habitat burial caused by a large-scale beach nourishment. Newly settled Haemulon spp. represented the most abundant fish taxa on NHB. Populations of this life-history stage exhibited high variability among annual surveys and no direct effect of NHB burial was detected. In contrast, early juvenile individuals showed a significant decline during the annual survey corresponding with the timing of the beach construction (burial of NHB habitat). Furthermore, the beach-nourishment activities altered the entire fish assemblage structure of the NHB adjacent to the beach fill area. This change in the NHB fish assemblage structure had not returned to pre-impact conditions three years after the conclusion of the nourishment. Limestone boulder reefs deployed to mitigate for buried habitat exhibited lower newly settled Haemulon spp. abundance than NHB. Contrastingly, early juvenile abundance was higher on the boulder reefs than on the NHB. Fish assemblage structure on the boulder reefs differed substantially from the NHB for which it was intended to resemble; with more mid- and large-bodied predators present on the boulder reefs. The results suggest mitigation boulder reefs did not provide equitable settlement habitat for Haemulon spp. Based on the combined results of this dissertation, it appears that shallow reef habitats (especially NHB) represent important settlement habitat for Haemulon spp. by providing spatial refuge from predators, which were more prevalent at deeper sites. Although burial did not appear to directly cause changes to newly settled Haemulon spp. populations on the NHB, fish assemblage structure was altered. Changes in species composition and abundance can have unforeseen ecological consequences for future Haemulon spp. populations. Relative to other reef habitats, the high densities of new settlers supported by the NHB suggests this unique habitat deserves protection from future nthropogenic impacts.
|
Page generated in 0.0634 seconds