Pub Date : 2024-01-10DOI: 10.47193/mafis.37x2024010106
Gabriela Mora-Rojas, Eric J. Alfaro
The low-level circulation of the atmosphere over Isla del Coco has been studied and the presence of a northerly wind at low levels of the atmosphere in the eastern tropical Pacific, in addition to the deep Hadley circulation cell, has been confirmed. Using data from pilot balloons (May 1997 through January 1999, October 2007 through April 2008), the northern flow is between 1 and 5 km high, depending on the time of year, with a maximum speed located between 2 and 3 km above the surface. The generating mechanism of the surface return flow in the Hadley circulation cell has been formulated as a sea breeze, Ekman pumping of the boundary layer, and it could even be a response to the Rossby wave generated by warming in the Chocó region. These results agree with those obtained from the ERA5 reanalysis (January 1979 through December 2020), which show that the southern return cell varies in position and height during the course of the year, with a poorly organized circulation in March and strengthening from July to February. The incorporation of data of low, medium and high cloud cover from Year of the Tropical Convection (boreal summer 2009) evidenced the presence of high-level clouds in the ITCZ region and low-level clouds to the south of the ITCZ, latitudes where the south surface circulation cell is located.
{"title":"An observational analysis of the eastern tropical Pacific Shallow Meridional Circulation using YOTC data and pilot balloons from Isla del Coco, Costa Rica","authors":"Gabriela Mora-Rojas, Eric J. Alfaro","doi":"10.47193/mafis.37x2024010106","DOIUrl":"https://doi.org/10.47193/mafis.37x2024010106","url":null,"abstract":"The low-level circulation of the atmosphere over Isla del Coco has been studied and the presence of a northerly wind at low levels of the atmosphere in the eastern tropical Pacific, in addition to the deep Hadley circulation cell, has been confirmed. Using data from pilot balloons (May 1997 through January 1999, October 2007 through April 2008), the northern flow is between 1 and 5 km high, depending on the time of year, with a maximum speed located between 2 and 3 km above the surface. The generating mechanism of the surface return flow in the Hadley circulation cell has been formulated as a sea breeze, Ekman pumping of the boundary layer, and it could even be a response to the Rossby wave generated by warming in the Chocó region. These results agree with those obtained from the ERA5 reanalysis (January 1979 through December 2020), which show that the southern return cell varies in position and height during the course of the year, with a poorly organized circulation in March and strengthening from July to February. The incorporation of data of low, medium and high cloud cover from Year of the Tropical Convection (boreal summer 2009) evidenced the presence of high-level clouds in the ITCZ region and low-level clouds to the south of the ITCZ, latitudes where the south surface circulation cell is located.","PeriodicalId":505082,"journal":{"name":"Marine and Fishery Sciences (MAFIS)","volume":"55 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139441124","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}
Pub Date : 2024-01-10DOI: 10.47193/mafis.37x2024010109
Maite Sánchez Acosta, Noemí Góngora, Diego Antuña, Patricia Correa, Ernesto Chiesa, E. Brugnoli, Pablo Muniz
Rapana venosa, a gastropod of Asian origin, has become a highly successful invasive species in various coastal-estuarine ecosystems worldwide. It was first recorded in the Río de la Plata (RdlP) in 1999 and has since expanded its range along the Argentine and Uruguayan Atlantic coast, and recently in southern Brazil. This study collected R. venosa samples during spring 2017 in the RdlP (middle/outer) and on the Uruguayan coast of the Argentine-Uruguayan Common Fishing Zone. The study found that 16% of stations surveyed contained R. venosa specimens with a density of 3.88 kg mn-2. Among the 119 specimens analyzed, males predominated, and imposex was observed in two organisms. Most individuals had a high epibiont coverage, and 10% were found consuming native bivalves. Isotopic analysis (d15N and d13C) in 80 individuals revealed no significant differences in location or sex, and the species was classified as secondary consumer with a trophic level (TL) of 2.5. This study provides valuable insights into the population dynamics of R. venosa and its ecological impact on the RdlP, emphasizing its successful invasion and effects on native mollusks. Further research is required to understand the long-term consequences of this invasive species on local and regional ecosystems.
Rapana venosa 是一种源于亚洲的腹足类动物，已成为全球各种沿海-河口生态系统中非常成功的入侵物种。1999 年，拉普拉塔河（RdlP）首次记录到该物种，此后，它的分布范围沿阿根廷和乌拉圭大西洋海岸扩展，最近还扩展到了巴西南部。本研究于 2017 年春季在拉普拉塔河（中游/外游）和阿根廷-乌拉圭共同捕鱼区的乌拉圭海岸采集了 R. venosa 样本。研究发现，16%的调查站点含有R. venosa标本，密度为3.88 kg mn-2。在分析的 119 个标本中，雄性占多数，在两个生物体内观察到了外生性。大多数个体的附肢覆盖率较高，10%的个体食用本地双壳贝类。对 80 个个体进行的同位素分析（d15N 和 d13C）显示，它们的位置和性别没有显著差异，该物种被归类为二级消费者，营养级（TL）为 2.5。这项研究提供了关于R. venosa种群动态及其对RdlP生态影响的宝贵见解，强调了它的成功入侵及其对本地软体动物的影响。要了解这种入侵物种对当地和区域生态系统的长期影响，还需要进一步的研究。
{"title":"An update of the invasion status of Rapana venosa (Mollusca: Gastropoda) in the Río de la Plata estuary","authors":"Maite Sánchez Acosta, Noemí Góngora, Diego Antuña, Patricia Correa, Ernesto Chiesa, E. Brugnoli, Pablo Muniz","doi":"10.47193/mafis.37x2024010109","DOIUrl":"https://doi.org/10.47193/mafis.37x2024010109","url":null,"abstract":"Rapana venosa, a gastropod of Asian origin, has become a highly successful invasive species in various coastal-estuarine ecosystems worldwide. It was first recorded in the Río de la Plata (RdlP) in 1999 and has since expanded its range along the Argentine and Uruguayan Atlantic coast, and recently in southern Brazil. This study collected R. venosa samples during spring 2017 in the RdlP (middle/outer) and on the Uruguayan coast of the Argentine-Uruguayan Common Fishing Zone. The study found that 16% of stations surveyed contained R. venosa specimens with a density of 3.88 kg mn-2. Among the 119 specimens analyzed, males predominated, and imposex was observed in two organisms. Most individuals had a high epibiont coverage, and 10% were found consuming native bivalves. Isotopic analysis (d15N and d13C) in 80 individuals revealed no significant differences in location or sex, and the species was classified as secondary consumer with a trophic level (TL) of 2.5. This study provides valuable insights into the population dynamics of R. venosa and its ecological impact on the RdlP, emphasizing its successful invasion and effects on native mollusks. Further research is required to understand the long-term consequences of this invasive species on local and regional ecosystems.","PeriodicalId":505082,"journal":{"name":"Marine and Fishery Sciences (MAFIS)","volume":"4 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139439196","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}
Pub Date : 2023-12-27DOI: 10.47193/mafis.37x2024010112
Greg Crawford, Matthew Mepstead, Edgardo Díaz-Ferguson
Coiba Island and the associated Special Zone of Marine Protection represent an important, yet poorly studied marine reserve along the Pacific coast of Panama. While efforts have recently began to establish monitoring programs in the region, a range of historical, marine-related environmental measurements already exist, derived from satellite-based observations. The goal of this paper was to use long-term datasets for key variables to provide qualitative insights (i.e. descriptive oceanography) of climatological conditions and interannual variability in the Pacific Panama region. These are underpinned with numerical assessments, providing an important baseline for ongoing and future studies, particularly in the Coiba Island/Gulf of Chiriqui region. In particular, we examined 20 years (January 2003-December 2022) of wind stress, sea surface temperature (SST), and chlorophyll-a (Chl-a), spanning the neritic and pelagic regions of the Pacific Panama coast. During the dry season (northern winter), the well-known, seasonal, regional Panama wind jet appeared across the Gulf of Panama, leading to surface mixing and SST cooling that eventually extended across most of the Panama Bight. West of the Azuero Peninsula, SST increased and surface warming extended further offshore from January through April. The SST in the Gulf of Chiriqui during this period was about 1 °C warmer on average than east of Coiba Island. By July and August, offshore SST gradients became largely longitudinal, cooling occured across the season, and the SST on either side of Coiba Island was nearly the same. The influence of the Panama jet in the Gulf of Panama was clear in the Chl-a data as well, with upwelling-driven values peaking in February/March (up to 11 mg m-3, with a monthly climatological value of around 2 mg m-3 during this period). During the rest of the year, the Chl-a concentration in this region averaged around 0.5-1.0 mg m-3. In the Gulf of Chiriqui and the region east of Coiba Island, the climatological monthly averages were roughly 0.3-0.5 mg m-3 and 0.4-0.6 mg m-3, respectively. Somewhat surprisingly, very high Chl-a values were present in the satellite data for the Gulf of Chiriqui during May 2007 and June 2008, peaking at 16 mg m-3 and 32 mg m-3 at a location just west of Coiba Island, respectively. It remains unclear as to the cause of these apparent blooms. Even when the high Chl-a values were excluded in the calculation of climatological averages in the Gulf of Chiriqui, however, there is a suggestion of modest seasonality in Chl-a values, with slightly elevated values (~ 0.4 mg m-3) peaking around May and October. During the extreme El Niño event of 2015-2016, the monthly-averaged SST along the Panama Pacific coast was warmer than average, with elevated levels of up to + 2 °C and lasting 12 months in the Gulf of Chiriqui. In the Gulf of Panama, the monthly-averaged SST anomalies were up to + 1.7 °C, although the temperatures returned to near-seasonal averages af
{"title":"Characterizing oceanographic conditions near Coiba Island and Pacific Panama using 20 years of satellite-based wind stress, SST and chlorophyll-a measurements","authors":"Greg Crawford, Matthew Mepstead, Edgardo Díaz-Ferguson","doi":"10.47193/mafis.37x2024010112","DOIUrl":"https://doi.org/10.47193/mafis.37x2024010112","url":null,"abstract":"Coiba Island and the associated Special Zone of Marine Protection represent an important, yet poorly studied marine reserve along the Pacific coast of Panama. While efforts have recently began to establish monitoring programs in the region, a range of historical, marine-related environmental measurements already exist, derived from satellite-based observations. The goal of this paper was to use long-term datasets for key variables to provide qualitative insights (i.e. descriptive oceanography) of climatological conditions and interannual variability in the Pacific Panama region. These are underpinned with numerical assessments, providing an important baseline for ongoing and future studies, particularly in the Coiba Island/Gulf of Chiriqui region. In particular, we examined 20 years (January 2003-December 2022) of wind stress, sea surface temperature (SST), and chlorophyll-a (Chl-a), spanning the neritic and pelagic regions of the Pacific Panama coast. During the dry season (northern winter), the well-known, seasonal, regional Panama wind jet appeared across the Gulf of Panama, leading to surface mixing and SST cooling that eventually extended across most of the Panama Bight. West of the Azuero Peninsula, SST increased and surface warming extended further offshore from January through April. The SST in the Gulf of Chiriqui during this period was about 1 °C warmer on average than east of Coiba Island. By July and August, offshore SST gradients became largely longitudinal, cooling occured across the season, and the SST on either side of Coiba Island was nearly the same. The influence of the Panama jet in the Gulf of Panama was clear in the Chl-a data as well, with upwelling-driven values peaking in February/March (up to 11 mg m-3, with a monthly climatological value of around 2 mg m-3 during this period). During the rest of the year, the Chl-a concentration in this region averaged around 0.5-1.0 mg m-3. In the Gulf of Chiriqui and the region east of Coiba Island, the climatological monthly averages were roughly 0.3-0.5 mg m-3 and 0.4-0.6 mg m-3, respectively. Somewhat surprisingly, very high Chl-a values were present in the satellite data for the Gulf of Chiriqui during May 2007 and June 2008, peaking at 16 mg m-3 and 32 mg m-3 at a location just west of Coiba Island, respectively. It remains unclear as to the cause of these apparent blooms. Even when the high Chl-a values were excluded in the calculation of climatological averages in the Gulf of Chiriqui, however, there is a suggestion of modest seasonality in Chl-a values, with slightly elevated values (~ 0.4 mg m-3) peaking around May and October. During the extreme El Niño event of 2015-2016, the monthly-averaged SST along the Panama Pacific coast was warmer than average, with elevated levels of up to + 2 °C and lasting 12 months in the Gulf of Chiriqui. In the Gulf of Panama, the monthly-averaged SST anomalies were up to + 1.7 °C, although the temperatures returned to near-seasonal averages af","PeriodicalId":505082,"journal":{"name":"Marine and Fishery Sciences (MAFIS)","volume":"123 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139153918","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}
Pub Date : 2023-11-16DOI: 10.47193/mafis.3722024010501
René Zambrano, Dialhy Coello, Marco Herrera
The objective of the present work was to establish modal lengths, empirical lengths at sexual maturity, and proportions of mature individuals of six deep-sea species from the bycatch of the experimental fishery for Patagonian toothfish (Dissostichus eleginoides). Fishing was conducted in Ecuadorian oceanic waters by only one vessel, between 2017 and 2021. Modal lengths were identified using frequency distributions. The length at sexual maturity (Lm) was estimated using the empirical equation: Ln Lm = -0.1189 + 0.9157 * Ln (Lmax). Modal lengths presented a little annual increment in Antimora rostrata and Coryphaenoides armatus while the values decreased for Centroscymnus owstonii, C. delsolari, and Hydrolagus melanophasma. Interannual lengths were similar for Etmopterus granulosus. Modal lengths were higher than the sexual maturity length for H. melanophasma, C. delsolari, C. owstonii and A. rostrata. Furthermore, Coryphaenoides armatus showed a similar value and E. granulosus a lower modal length. Empirical length at sexual maturity was between 56.35 and 66.26 cm TL for all species except for H. melanophasma, which was 100.53 cm TL. Antimora rostrata and C. armatus presented an increment of mature individuals while the annual percentage decreased for H. melanophasma, C. owstonii, and C. delsolari. Etmopterus granulosus showed a lower proportion of mature individuals.
本研究的目的是从巴塔哥尼亚齿鱼（Dissostichus eleginoides）试验性捕捞的副渔获物中确定六个深海物种的模态长度、性成熟时的经验长度和成熟个体的比例。2017 年至 2021 年期间，只有一艘渔船在厄瓜多尔大洋水域进行捕捞。使用频率分布确定了模态长度。使用经验公式估算了性成熟时的长度（Lm）：Ln Lm = -0.1189 + 0.9157 * Ln (Lmax)。Antimora rostrata 和 Coryphaenoides armatus 的模态长度每年略有增加，而 Centroscymnus owstonii、C. delsolari 和 Hydrolagus melanophasma 的模态长度则有所减少。粒翅鱼（Etmopterus granulosus）的年际长度相似。H. melanophasma、C. delsolari、C. owstonii 和 A. rostrata 的模态长度高于性成熟长度。此外，Coryphaenoides armatus 的模态长度与之相近，而 E. granulosus 的模态长度较低。除了 H. melanophasma 的经验总长为 100.53 cm TL 外，其他物种性成熟时的经验总长都在 56.35 到 66.26 cm TL 之间。Antimora rostrata 和 C. armatus 的成熟个体数量在增加，而 H. melanophasma、C. owstonii 和 C. delsolari 的成熟个体数量则在减少。颗粒蝶（Etmopterus granulosus）的成熟个体比例较低。
{"title":"Modal and empirical lengths at sexual maturity for six deep-sea species in Ecuadorian oceanic waters","authors":"René Zambrano, Dialhy Coello, Marco Herrera","doi":"10.47193/mafis.3722024010501","DOIUrl":"https://doi.org/10.47193/mafis.3722024010501","url":null,"abstract":"The objective of the present work was to establish modal lengths, empirical lengths at sexual maturity, and proportions of mature individuals of six deep-sea species from the bycatch of the experimental fishery for Patagonian toothfish (Dissostichus eleginoides). Fishing was conducted in Ecuadorian oceanic waters by only one vessel, between 2017 and 2021. Modal lengths were identified using frequency distributions. The length at sexual maturity (Lm) was estimated using the empirical equation: Ln Lm = -0.1189 + 0.9157 * Ln (Lmax). Modal lengths presented a little annual increment in Antimora rostrata and Coryphaenoides armatus while the values decreased for Centroscymnus owstonii, C. delsolari, and Hydrolagus melanophasma. Interannual lengths were similar for Etmopterus granulosus. Modal lengths were higher than the sexual maturity length for H. melanophasma, C. delsolari, C. owstonii and A. rostrata. Furthermore, Coryphaenoides armatus showed a similar value and E. granulosus a lower modal length. Empirical length at sexual maturity was between 56.35 and 66.26 cm TL for all species except for H. melanophasma, which was 100.53 cm TL. Antimora rostrata and C. armatus presented an increment of mature individuals while the annual percentage decreased for H. melanophasma, C. owstonii, and C. delsolari. Etmopterus granulosus showed a lower proportion of mature individuals.","PeriodicalId":505082,"journal":{"name":"Marine and Fishery Sciences (MAFIS)","volume":"67 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139267188","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：