The regular echinoid Lytechinus variegatus is a valuable model for the study of early embryological development. Lytechinus variegatus inhabits nearshore seagrass beds in the Gulf of Mexico and Caribbean, and the species ranges from the Carolinas along the US Atlantic coast to Brazil. Evaluating the natural reproductive cycle of L. variegatus will aid in understanding its role in community structure and in the management of this resource when housed in the laboratory. From April 2001 to September 2003, at intervals of 4—6 weeks, L. variegatus (41−50 mm diameter; n = 32 individuals/collection) were collected at Eagle Harbor in St. Joseph’s Bay, FL. A histological staging system for gamete development and maturation of the gonad was devised for female and male L. variegatus. The annual minimum gonad index was observed in September or October and increased to a maximum in March or April. A period of nutrient storage and limited gametogenic activity along the germinal epithelium in the fall and winter preceded spring gamete production and maturation. Observations of the mature reproductive stage in L. variegatus were associated with the new and full moon, suggesting that lunar cycle or tides influenced the timing of spawning. Peak periods of spawning occurred in spring and, occasionally, in the summer. Spawning probably did not occur from October to January. These data indicate field collections can be timed for early spring to ensure gravid adults for developmental studies.
{"title":"A Histological Assessment of the Reproductive Cycle of the Sea Urchin, Lytechinus variegatus","authors":"Adele Cunningham, Victoria Gibbs, Stephen Watts","doi":"10.18785/gcr.3401.15","DOIUrl":"https://doi.org/10.18785/gcr.3401.15","url":null,"abstract":"The regular echinoid Lytechinus variegatus is a valuable model for the study of early embryological development. Lytechinus variegatus inhabits nearshore seagrass beds in the Gulf of Mexico and Caribbean, and the species ranges from the Carolinas along the US Atlantic coast to Brazil. Evaluating the natural reproductive cycle of L. variegatus will aid in understanding its role in community structure and in the management of this resource when housed in the laboratory. From April 2001 to September 2003, at intervals of 4—6 weeks, L. variegatus (41−50 mm diameter; n = 32 individuals/collection) were collected at Eagle Harbor in St. Joseph’s Bay, FL. A histological staging system for gamete development and maturation of the gonad was devised for female and male L. variegatus. The annual minimum gonad index was observed in September or October and increased to a maximum in March or April. A period of nutrient storage and limited gametogenic activity along the germinal epithelium in the fall and winter preceded spring gamete production and maturation. Observations of the mature reproductive stage in L. variegatus were associated with the new and full moon, suggesting that lunar cycle or tides influenced the timing of spawning. Peak periods of spawning occurred in spring and, occasionally, in the summer. Spawning probably did not occur from October to January. These data indicate field collections can be timed for early spring to ensure gravid adults for developmental studies.","PeriodicalId":36764,"journal":{"name":"GULF AND CARIBBEAN RESEARCH","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135710258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Data—limited stock assessment methods have the potential to positively impact livelihoods of fishermen around the world by providing management recommendations that aim to optimize sustainable yields from fisheries. Some years ago, a novel length— based (LB) method was developed for the assessment of spawning potential ratio (SPR), a measure of the reproductive capacity of fish stocks. We applied the LB—SPR method to 5 important target species of the coastal gillnet fishery in Guyana and Suriname. Nebris microps (Smalleye Croaker; 32% SPR) and Macrodon ancylodon (King Weakfish; 34% SPR) had the highest spawning potential, but remained below the 40% target level needed to ensure sustainable exploitation. Cynoscion acoupa (Acoupa Weakfish; 13% SPR), C. virescens (Green Weakfish; 11% SPR) and Hexanematichthys proops (Crucifix Sea Catfish; 14% SPR) had SPR values below the 20% limit reference point, indicating severe and potentially long—term population depletion. There are several sources of potential bias in our SPR estimates, including concerns over the length frequency dataset, potential violation of LB—SPR model assumptions and the poor estimation of certain life—history parameters. Based on our experiences, various recommendations are formulated to be considered in future stock assessment efforts in the region. While our results are preliminary and need careful interpretation, they are in line with anecdotal evidence that the demersal gillnet fishery in Guyana and Suriname is overexploiting the resources it depends upon. We recommend to implement precautionary fisheries management measures that aim to rebuild the stocks and improve their spawning potential.
{"title":"A Preliminary Assessment of the Spawning Potential Ratio of Five Target Species of the Coastal Gillnet Fishery in Guyana and Suriname","authors":"T. Willems, Elford A. Liverpool, Michael Hiwat","doi":"10.18785/gcr.3401.06","DOIUrl":"https://doi.org/10.18785/gcr.3401.06","url":null,"abstract":"Data—limited stock assessment methods have the potential to positively impact livelihoods of fishermen around the world by providing management recommendations that aim to optimize sustainable yields from fisheries. Some years ago, a novel length— based (LB) method was developed for the assessment of spawning potential ratio (SPR), a measure of the reproductive capacity of fish stocks. We applied the LB—SPR method to 5 important target species of the coastal gillnet fishery in Guyana and Suriname. Nebris microps (Smalleye Croaker; 32% SPR) and Macrodon ancylodon (King Weakfish; 34% SPR) had the highest spawning potential, but remained below the 40% target level needed to ensure sustainable exploitation. Cynoscion acoupa (Acoupa Weakfish; 13% SPR), C. virescens (Green Weakfish; 11% SPR) and Hexanematichthys proops (Crucifix Sea Catfish; 14% SPR) had SPR values below the 20% limit reference point, indicating severe and potentially long—term population depletion. There are several sources of potential bias in our SPR estimates, including concerns over the length frequency dataset, potential violation of LB—SPR model assumptions and the poor estimation of certain life—history parameters. Based on our experiences, various recommendations are formulated to be considered in future stock assessment efforts in the region. While our results are preliminary and need careful interpretation, they are in line with anecdotal evidence that the demersal gillnet fishery in Guyana and Suriname is overexploiting the resources it depends upon. We recommend to implement precautionary fisheries management measures that aim to rebuild the stocks and improve their spawning potential.","PeriodicalId":36764,"journal":{"name":"GULF AND CARIBBEAN RESEARCH","volume":"1 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67685452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Claire Legaspi, M. Barros, Alexandra R. Rodriguez, R. Baker
{"title":"Assessment of Living Shorelines for Restoring Fish Habitats: A Case Study from Coastal Alabama","authors":"Claire Legaspi, M. Barros, Alexandra R. Rodriguez, R. Baker","doi":"10.18785/gcr.3401.01","DOIUrl":"https://doi.org/10.18785/gcr.3401.01","url":null,"abstract":"","PeriodicalId":36764,"journal":{"name":"GULF AND CARIBBEAN RESEARCH","volume":"1 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67684574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Holopelagic Sargassum is a critical nursery habitat for the early life stages of many marine fishes, including several federally managed species in the United States and Caribbean. Sargassum is often aggregated along surface convergence features where microdebris (synthetic, semi—synthetic, and naturally—derived particles size) have also been found in relatively high concentrations. In this study, we collected microdebris from Sargassum and adjacent open water habitats (in 2018), and juvenile fishes from Sargassum (in 2017 and 2018) in the northern Gulf of Mexico to quantify habitat—specific microdebris concentrations and the degree to which Sargassum—associated juvenile fishes ingest microdebris. Microdebris concentrations within Sargassum habitats were, on average, 180 times greater than those found within adjacent open water habitats. Microdebris concentrations decreased with distance from shore in both Sargassum and open water habitats, and generally increased with Sargassum biomass. Microdebris ingestion by juvenile (9–320 mm SL) fishes (n = 846) varied by year (all taxa: 24.7% in 2017; 14.7% in 2018) and by taxa, and generally decreased with distance from shore. Small fibers were the dominant type of microdebris observed in stomach contents. The structural complexity of Sargassum provides a mechanism for microdebris capture and concentration in surface waters. Since 2011, massive blooms of Sargassum have inundated regions in the central Atlantic Ocean and Caribbean Sea. The role of Sargassum as a microdebris “sink” has major implications for the transport of microdebris as Sargassum drifts within and across basins and eventually strands on beaches and coastal habitats, or subsides to benthic environments.
全覆盖马尾藻是许多海洋鱼类早期生命阶段的重要苗圃栖息地，包括美国和加勒比地区的一些联邦管理物种。马尾藻通常沿着表面汇聚特征聚集，在那里也发现了相对高浓度的微碎屑(合成的、半合成的和天然衍生的颗粒大小)。在本研究中，我们收集了来自墨西哥湾北部马尾藻和邻近开放水域栖息地(2018年)的微碎片，以及马尾藻幼鱼(2017年和2018年)的微碎片，以量化栖息地特异性微碎片浓度以及马尾藻相关幼鱼摄入微碎片的程度。马尾藻栖息地内的微碎片浓度平均是邻近开阔水域栖息地的180倍。在马尾藻和开放水域生境中，微碎屑浓度随距离海岸的远近而降低，随马尾藻生物量的增加而增加。幼鱼(9-320 mm SL) (n = 846)的微碎片摄取量随年份而变化(2017年所有分类群:24.7%;14.7%(2018年)和分类群，并随着距离海岸的距离而普遍减少。在胃内容物中观察到的微碎片以小纤维为主。马尾藻结构的复杂性为微碎片在地表水的捕获和集中提供了一种机制。自2011年以来，马尾藻的大量繁殖淹没了大西洋中部和加勒比海地区。马尾藻作为微碎片“汇”的作用对微碎片的运输有重大影响，因为马尾藻在盆地内和跨盆地漂移，最终在海滩和沿海栖息地搁浅，或沉降到底栖环境。
{"title":"Microdebris Abundance, Distribution, and Ingestion by Sargassum-Associated Juvenile Fishes in the Gulf of Mexico","authors":"O. Lestrade, F. Hernandez","doi":"10.18785/gcr.3401.05","DOIUrl":"https://doi.org/10.18785/gcr.3401.05","url":null,"abstract":"Holopelagic Sargassum is a critical nursery habitat for the early life stages of many marine fishes, including several federally managed species in the United States and Caribbean. Sargassum is often aggregated along surface convergence features where microdebris (synthetic, semi—synthetic, and naturally—derived particles size) have also been found in relatively high concentrations. In this study, we collected microdebris from Sargassum and adjacent open water habitats (in 2018), and juvenile fishes from Sargassum (in 2017 and 2018) in the northern Gulf of Mexico to quantify habitat—specific microdebris concentrations and the degree to which Sargassum—associated juvenile fishes ingest microdebris. Microdebris concentrations within Sargassum habitats were, on average, 180 times greater than those found within adjacent open water habitats. Microdebris concentrations decreased with distance from shore in both Sargassum and open water habitats, and generally increased with Sargassum biomass. Microdebris ingestion by juvenile (9–320 mm SL) fishes (n = 846) varied by year (all taxa: 24.7% in 2017; 14.7% in 2018) and by taxa, and generally decreased with distance from shore. Small fibers were the dominant type of microdebris observed in stomach contents. The structural complexity of Sargassum provides a mechanism for microdebris capture and concentration in surface waters. Since 2011, massive blooms of Sargassum have inundated regions in the central Atlantic Ocean and Caribbean Sea. The role of Sargassum as a microdebris “sink” has major implications for the transport of microdebris as Sargassum drifts within and across basins and eventually strands on beaches and coastal habitats, or subsides to benthic environments.","PeriodicalId":36764,"journal":{"name":"GULF AND CARIBBEAN RESEARCH","volume":"1 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67684932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Joel D. Anderson, D. McDonald, Ethan Getz, Roberta Weixelman, Faye P. Grubbs, J. Ferguson
Recent population expansion of Gray Snapper, Lutjanus griseus, in the northern Gulf of Mexico is driving increasing catch in the recreational fishery in Texas. We assessed long—term trends in distribution and abundance of Gray Snapper in Texas using fishery—dependent and fishery—independent data collected by the Texas Parks and Wildlife Department in the years 1980 — 2019. Boosted regression trees (BRT) were used to evaluate factors (water quality, season, depth, bay and inlet distance) driving Gray Snapper presence in fishery—independent samples of juveniles (seines) and subadults (gill nets) found in estuaries. Estuarine Gray Snapper were subsequently sampled from gill nets, and otolith age and gonad development were evaluated microscopically to assess patterns of age, growth, and maturity. Increasing Gray Snapper abundance in Texas was coupled with expansion of the population age structure in comparisons before and after 1993. Gray Snapper juveniles and subadults encountered in Texas estuaries are generally associated with lower bays and offshore passes, and are more common in the late summer/early fall. Comparison of size (total length in mm) of recreational catch inshore versus offshore suggests that mature adults recruit to offshore habitats around 409 mm TL, or around 3 years old, which is approximately coincident with the onset of sexual maturity. Increasing abundance coupled with an expanding age structure of Gray Snapper in Texas have co—occurred with increasing winter temperatures over time. Population expansion could be facilitated by management measures that improve overwinter survival of juveniles and subadults in estuaries prior to offshore recruitment.
{"title":"Distribution, Maturity, Age and Growth of Gray Snapper (Lutjanus griseus) in the Northwestern Gulf of Mexico","authors":"Joel D. Anderson, D. McDonald, Ethan Getz, Roberta Weixelman, Faye P. Grubbs, J. Ferguson","doi":"10.18785/gcr.3301.02","DOIUrl":"https://doi.org/10.18785/gcr.3301.02","url":null,"abstract":"Recent population expansion of Gray Snapper, Lutjanus griseus, in the northern Gulf of Mexico is driving increasing catch in the recreational fishery in Texas. We assessed long—term trends in distribution and abundance of Gray Snapper in Texas using fishery—dependent and fishery—independent data collected by the Texas Parks and Wildlife Department in the years 1980 — 2019. Boosted regression trees (BRT) were used to evaluate factors (water quality, season, depth, bay and inlet distance) driving Gray Snapper presence in fishery—independent samples of juveniles (seines) and subadults (gill nets) found in estuaries. Estuarine Gray Snapper were subsequently sampled from gill nets, and otolith age and gonad development were evaluated microscopically to assess patterns of age, growth, and maturity. Increasing Gray Snapper abundance in Texas was coupled with expansion of the population age structure in comparisons before and after 1993. Gray Snapper juveniles and subadults encountered in Texas estuaries are generally associated with lower bays and offshore passes, and are more common in the late summer/early fall. Comparison of size (total length in mm) of recreational catch inshore versus offshore suggests that mature adults recruit to offshore habitats around 409 mm TL, or around 3 years old, which is approximately coincident with the onset of sexual maturity. Increasing abundance coupled with an expanding age structure of Gray Snapper in Texas have co—occurred with increasing winter temperatures over time. Population expansion could be facilitated by management measures that improve overwinter survival of juveniles and subadults in estuaries prior to offshore recruitment.","PeriodicalId":36764,"journal":{"name":"GULF AND CARIBBEAN RESEARCH","volume":"1 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67684275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Over the past decade unprecedented blooming of pelagic Sargassum has occurred across the Equatorial Atlantic from West Africa to the Caribbean. Although pelagic Sargassum mats are considered beneficial in the open ocean, providing valuable habitat for a diverse array of endemic and associated species, they also inundate coastal areas and cause a plethora of management challenges for fisheries, tourism, nearshore coastal ecosystems, public health and the socioeconomic welfare of coastal communities. In—water harvesting has been suggested as a desirable management solution to prevent shoreline inundation, but destruction of the associated biodiversity is a concern with this approach and has not been adequately examined. Furthermore, in—water harvesting methods within the Tropical Atlantic and Caribbean have been ad hoc and highly variable with no established sampling protocol. Here we review 30 published studies detailing methods to collect information on the biodiversity associated with pelagic Sargassum. Nets, hook and line, video recordings, bare—hands and plastic bags have all been used to collect epiphytic, clinging and free—swimming fauna associated with Sargassum. Net sampling was the predominant method; however, in the absence of a standardized approach a wide range of net types and sizes were used. Similarly, separation, identification and preservation methods were all unstandardized. This review highlights the need for standardization and provides the first set of guidelines for the collection and assessment of Sargassum—associated biodiversity. Nevertheless, these approaches are labor intensive and require extensive replication in time and space to produce a reasonable assessment of the biodiversity associated with the Sargassum community.
{"title":"How is Pelagic Sargassum-Associated Biodiversity Assessed? Insights from the Literature","authors":"Kristie S. T. Alleyne","doi":"10.18785/gcr.3301.08","DOIUrl":"https://doi.org/10.18785/gcr.3301.08","url":null,"abstract":"Over the past decade unprecedented blooming of pelagic Sargassum has occurred across the Equatorial Atlantic from West Africa to the Caribbean. Although pelagic Sargassum mats are considered beneficial in the open ocean, providing valuable habitat for a diverse array of endemic and associated species, they also inundate coastal areas and cause a plethora of management challenges for fisheries, tourism, nearshore coastal ecosystems, public health and the socioeconomic welfare of coastal communities. In—water harvesting has been suggested as a desirable management solution to prevent shoreline inundation, but destruction of the associated biodiversity is a concern with this approach and has not been adequately examined. Furthermore, in—water harvesting methods within the Tropical Atlantic and Caribbean have been ad hoc and highly variable with no established sampling protocol. Here we review 30 published studies detailing methods to collect information on the biodiversity associated with pelagic Sargassum. Nets, hook and line, video recordings, bare—hands and plastic bags have all been used to collect epiphytic, clinging and free—swimming fauna associated with Sargassum. Net sampling was the predominant method; however, in the absence of a standardized approach a wide range of net types and sizes were used. Similarly, separation, identification and preservation methods were all unstandardized. This review highlights the need for standardization and provides the first set of guidelines for the collection and assessment of Sargassum—associated biodiversity. Nevertheless, these approaches are labor intensive and require extensive replication in time and space to produce a reasonable assessment of the biodiversity associated with the Sargassum community.","PeriodicalId":36764,"journal":{"name":"GULF AND CARIBBEAN RESEARCH","volume":"1 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67684834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jonathan Jackson, Yee Lau, Paul F. Mickle, J. Cebrian
{"title":"Temporal and Spatial Occurrence of Karenia brevis Blooms in the Northcentral Gulf of Mexico","authors":"Jonathan Jackson, Yee Lau, Paul F. Mickle, J. Cebrian","doi":"10.18785/gcr.3301.05","DOIUrl":"https://doi.org/10.18785/gcr.3301.05","url":null,"abstract":"","PeriodicalId":36764,"journal":{"name":"GULF AND CARIBBEAN RESEARCH","volume":"1 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67684048","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Anna Millender, Jeremy M. Higgs, N. Brown‐Peterson, Michael J. Andres, J. Franks
The current study examined 93 Swordfish, Xiphias gladius, (64 females, 27 males, 2 unknown) ranging in size from 77.6–246.3 cm lower jaw fork length (LJFL) from the northern Gulf of Mexico (GOM). Samples were collected between March and August in 2005–2007, 2017–2019 and 2021. Age estimates of 51 Swordfish resulted in a maximum observed age of 11 years (205.0 cm LJFL) and 7 years (190.4 cm LJFL) for females and males, respectively. Observed and back—calculated length—at—age data were fitted to 4 growth models (2— and 3— parameter von Bertalanffy, Gompertz, and logistic). The 2—parameter von Bertalanffy was the model that best fit the data (Linf = 210.2 cm LJFL, k = 0.25). Histological examination of gonadal tissue from 91 fish indicated that females reached 50% and 95% physiological maturity at 116 ± 6 cm LJFL and 143 ± 8 cm LJFL, respectively, corresponding to ages 2—3 years. All males >82 cm LJFL were physiologically sexually mature. Only 10% of females were reproductively active, with spawning capable females captured in June. Reproductively active females exhibited asynchronous oocyte development indicating batch spawning. Most males (96%) were spawning capable from April–August. Philometra sp. infection was found in all ovaries examined (n = 16) but with low abundance (2.25 ± 0.42); male philometrids were more prevalent than females (91.7% and 66.7%, respectively). Swordfish in the northern GOM appear to achieve sexual maturity at a younger age, grow faster, and have shorter theoretical longevity than previous reports from other regions world—wide.
目前的研究调查了来自墨西哥湾北部的93条剑鱼，剑鱼属Xiphias gladius，(64条雌性，27条雄性，2条未知)，大小在77.6-246.3厘米的下颌叉长(LJFL)之间。样本是在2005-2007年、2017-2019年和2021年的3月至8月间收集的。对51条剑鱼的年龄估计结果显示，雌性和雄性的最大观察年龄分别为11岁(205.0 cm LJFL)和7岁(190.4 cm LJFL)。观察到的和反向计算的年龄长度数据拟合到4个生长模型中(2参数和3参数von Bertalanffy、Gompertz和logistic)。2参数von Bertalanffy模型是最适合数据的模型(Linf = 210.2 cm LJFL, k = 0.25)。91条鱼的性腺组织组织学检查表明，雌性在116±6 cm LJFL和143±8 cm LJFL分别达到50%和95%的生理成熟度，对应年龄为2-3岁。所有LJFL小于82 cm的雄性生理性成熟。只有10%的雌性具有繁殖活性，有产卵能力的雌性在6月份被捕获。生殖活跃的雌性表现出异步卵母细胞发育，表明批量产卵。大多数雄鱼(96%)在4 - 8月产卵。所有卵巢均有Philometra感染(n = 16)，但丰度较低(2.25±0.42);雄性比雌性多(分别为91.7%和66.7%)。墨西哥湾北部的剑鱼似乎在更年轻的年龄达到性成熟，生长更快，并且比世界其他地区的先前报告的理论寿命更短。
{"title":"Life History of Swordfish, Xiphias gladius, Caught in the Northern Gulf of Mexico","authors":"Anna Millender, Jeremy M. Higgs, N. Brown‐Peterson, Michael J. Andres, J. Franks","doi":"10.18785/gcr.3301.09","DOIUrl":"https://doi.org/10.18785/gcr.3301.09","url":null,"abstract":"The current study examined 93 Swordfish, Xiphias gladius, (64 females, 27 males, 2 unknown) ranging in size from 77.6–246.3 cm lower jaw fork length (LJFL) from the northern Gulf of Mexico (GOM). Samples were collected between March and August in 2005–2007, 2017–2019 and 2021. Age estimates of 51 Swordfish resulted in a maximum observed age of 11 years (205.0 cm LJFL) and 7 years (190.4 cm LJFL) for females and males, respectively. Observed and back—calculated length—at—age data were fitted to 4 growth models (2— and 3— parameter von Bertalanffy, Gompertz, and logistic). The 2—parameter von Bertalanffy was the model that best fit the data (Linf = 210.2 cm LJFL, k = 0.25). Histological examination of gonadal tissue from 91 fish indicated that females reached 50% and 95% physiological maturity at 116 ± 6 cm LJFL and 143 ± 8 cm LJFL, respectively, corresponding to ages 2—3 years. All males >82 cm LJFL were physiologically sexually mature. Only 10% of females were reproductively active, with spawning capable females captured in June. Reproductively active females exhibited asynchronous oocyte development indicating batch spawning. Most males (96%) were spawning capable from April–August. Philometra sp. infection was found in all ovaries examined (n = 16) but with low abundance (2.25 ± 0.42); male philometrids were more prevalent than females (91.7% and 66.7%, respectively). Swordfish in the northern GOM appear to achieve sexual maturity at a younger age, grow faster, and have shorter theoretical longevity than previous reports from other regions world—wide.","PeriodicalId":36764,"journal":{"name":"GULF AND CARIBBEAN RESEARCH","volume":"1 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67684955","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Burrowing behavior of marsh periwinkles Littoraria irrorata in response to predator cues","authors":"Diere Hodges, Armorel Eason, D. Smee","doi":"10.18785/gcr.3301.10","DOIUrl":"https://doi.org/10.18785/gcr.3301.10","url":null,"abstract":"","PeriodicalId":36764,"journal":{"name":"GULF AND CARIBBEAN RESEARCH","volume":"1 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67685000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Landers, Kellan Hoffman, Nuria Sánchez, M. Sørensen
Sediment collections from the southern Gulf of Mexico between the Texas—Mexico border and the Yucatán Peninsula have resulted in many new kinorhynch species distribution records and the finding and taxonomic description of a new species, Dracoderes chaac sp. nov. This study focused on the non—echinoderid members of the Phylum Kinorhyncha, many of which are rare or restricted to only a few locations. A total of 136 specimens were identified from 24 sediment stations, distributed among the following species: Antygomonas gwenae, Campyloderes vanhoeffeni, Centroderes readae, Condyloderes flosfimbriatus, Co. rohalorum, Cristaphyes panamensis, Dracoderes chaac sp. nov., Leiocanthus corrugatus, L. langi, L. quinquenudus, L. satanicus, Pycnophyes alexandroi, Semnoderes lusca, and Sphenoderes aspidochelone. Additional undescribed species in the genera Leiocanthus, Mixtophyes, and Paracentrophyes were recovered. Statistical analysis of the stations revealed a grouping of locations where the majority of the pycnophyid species were recovered. Some species (e.g., Ca. vanhoeffeni, S. aspidochelone) had an extensive distribution, while others were recorded from one or few locations only (e.g., A. gwenae, Co. rohalorum). Most of the species were reported from earlier collections in the northern Gulf of Mexico on the U.S. continental shelf, between 700–1100 km away.
{"title":"Kinorhynch diversity in the southern Gulf of Mexico and a description of Dracoderes chaac sp. nov.","authors":"S. Landers, Kellan Hoffman, Nuria Sánchez, M. Sørensen","doi":"10.18785/gcr.3301.01","DOIUrl":"https://doi.org/10.18785/gcr.3301.01","url":null,"abstract":"Sediment collections from the southern Gulf of Mexico between the Texas—Mexico border and the Yucatán Peninsula have resulted in many new kinorhynch species distribution records and the finding and taxonomic description of a new species, Dracoderes chaac sp. nov. This study focused on the non—echinoderid members of the Phylum Kinorhyncha, many of which are rare or restricted to only a few locations. A total of 136 specimens were identified from 24 sediment stations, distributed among the following species: Antygomonas gwenae, Campyloderes vanhoeffeni, Centroderes readae, Condyloderes flosfimbriatus, Co. rohalorum, Cristaphyes panamensis, Dracoderes chaac sp. nov., Leiocanthus corrugatus, L. langi, L. quinquenudus, L. satanicus, Pycnophyes alexandroi, Semnoderes lusca, and Sphenoderes aspidochelone. Additional undescribed species in the genera Leiocanthus, Mixtophyes, and Paracentrophyes were recovered. Statistical analysis of the stations revealed a grouping of locations where the majority of the pycnophyid species were recovered. Some species (e.g., Ca. vanhoeffeni, S. aspidochelone) had an extensive distribution, while others were recorded from one or few locations only (e.g., A. gwenae, Co. rohalorum). Most of the species were reported from earlier collections in the northern Gulf of Mexico on the U.S. continental shelf, between 700–1100 km away.","PeriodicalId":36764,"journal":{"name":"GULF AND CARIBBEAN RESEARCH","volume":"1 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67684175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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