Cirilo O . Ybañez Jr. | Davao Oriental State College of Science and Technology (original) (raw)
Papers by Cirilo O . Ybañez Jr.
Davao research journal, May 8, 2024
Copepods are essential components of marine ecosystems, facilitating energy transfer within these... more Copepods are essential components of marine ecosystems, facilitating energy transfer within these complex systems. The study investigates copepod diversity and distribution in Ban-ao and Lambajon coastal areas in Baganga, Davao Oriental, highlighting the environmental factors influencing copepod populations. Four copepod families representing different orders were identified, with Harpacticoida, Calanoida, and Cyclopoida prevalent in both sites, while Misophrioida was exclusive to Lambajon. Physico-chemical parameters such as dissolved oxygen (DO), pH, salinity, sediment composition, water depth, and temperature were analyzed to understand their correlation with copepod density. The study reveals variations in copepod density and abundance between the sites, with Lambajon showing a higher total density (49 ind/cm³) compared to Ban-ao (35 ind/cm³). The Pearson correlation matrix illustrates complex relationships between copepod density and environmental parameters in each site. In Ban-ao, strong positive correlations were found between copepod density and DO (r = 0.65) and temperature (r = 0.36). In Lambajon, positive correlations existed between water depth and copepod density (r = 0.20). Both sites exhibit low copepod diversity overall, potentially due to anthropogenic pressures. These findings emphasize the need for further research to understand the interactions between environmental factors and copepod diversity, essential for effective conservation and management strategies in these coastal ecosystems.
Davao Research Journal
Asia is widely recognized for its grouper aquaculture. China (65%), Taiwan (17%), and Indonesia (... more Asia is widely recognized for its grouper aquaculture. China (65%), Taiwan (17%), and Indonesia (11%) together account for 93% of global grouper production. This study recorded 48 species, and 16 hybrids were used in Asian aquaculture. The conservation status of cultured grouper species is 67% least concern, 17% data deficient, 10% vulnerable, and 2% critically endangered, endangered, and near threatened. Most Asian countries face issues such as (1) lack of hatcheries, (2) poor seed stock, (3) poor broodstock quality, (4) lack of financial and technical support, (5) trash fish and accessibility to fish pellets, (6) poor water quality, (7) diseases, and (8) capture-based aquaculture. These issues, combined with overfishing, contribute to a decline in grouper productivity and their wild population. The decline has alarmed experts and conservationists looking into the causes and potential remedies to this problem. Some management strategies mentioned in this paper include: (1) closed s...
Davao Research Journal
The present study investigated the composition, density, abundance, and diversity of benthic fora... more The present study investigated the composition, density, abundance, and diversity of benthic foraminifera, and their relationship with various physico-chemical parameters such as pH, salinity, temperature, and sediment grain size. Foraminifera were collected from the intertidal zone using sediment cores and extracted from the sediments through sieving. The extracted foraminifera were stained with Rose bengal solution and preserved with buffered formalin. A total of 9,459 individuals of foraminifera were identified, consisting of 39 species classified into four orders, 16 families, and 21 genera. The top three most abundant genera were Calcarina, Baculogypsina, and Amphistegina. The comparison (ANOVA) of the abundance of foraminifera among the six stations revealed highly significant differences (P= 0.000; df= 38). Station 1 exhibited the highest diversity of foraminifera on Pujada Island, as indicated by an H’ value of 3.06. Conversely, station 6 displayed the lowest diversity, with...
Biodiversitas, 2024
This study explores the meiofaunal communities within Pujada Bay's intertidal zone, Philippines, ... more This study explores the meiofaunal communities within Pujada Bay's intertidal zone, Philippines, meticulously recording 18,193 individuals across 18 taxa. Differences in composition and abundance across sites were observed, with conservation efforts at Guang-guang yielding higher densities (4,613 ind/10 cm-2) compared to less-managed sites such as Magsaysay (928 ind/10 cm-2) and Badas (1,438 ind/10 cm-2). Furthermore, Macambol, distant from direct threats, exhibited notable densities (4,483 ind/10 cm-2), indicating the importance of geographic isolation in ecosystem preservation. Dominant taxa include Nematoda (41%), Copepoda (28%), Foraminifera (22%), and Polychaeta (5%), underscoring their ecological significance in Pujada Bay's meiofaunal community. These findings highlight the efficacy of conservation measures in fostering resilient meiofaunal communities, where management strategies and geographic location play vital roles in biodiversity preservation. This rese arch offers valuable insights into the ecological dynamics of Pujada Bay, emphasizing the indispensable role of conservation in maintaining biodiversity. By elucidating meiofaunal dynamics, this study advances our understanding of the local marine ecosystem and lays the groundwork for broader discussions on marine conservation strategies. Pujada Bay, considered one of the most beautiful bays i n the world, exemplifies the delicate balance between human activities and the imperative of preserving biodiversity in marine environments.
Davao Research Journal, 2024
Copepods are essential components of marine ecosystems, facilitating energy transfer within these... more Copepods are essential components of marine ecosystems, facilitating energy transfer within these complex systems. The study investigates copepod diversity and distribution in Ban-ao and Lambajon coastal areas in Baganga, Davao Oriental, highlighting the environmental factors influencing copepod populations. Four copepod families representing different orders were identified, with Harpacticoida, Calanoida, and Cyclopoida prevalent in both sites, while Misophrioida was exclusive to Lambajon. Physico-chemical parameters such as dissolved oxygen (DO), pH, salinity, sediment composition, water depth, and temperature were analyzed to understand their correlation with copepod density. The study reveals variations in copepod density and abundance between the sites, with Lambajon showing a higher total density (49 ind/cm³) compared to Ban-ao (35 ind/cm³). The Pearson correlation matrix illustrates complex relationships between copepod density and environmental parameters in each site. In Ban-ao, strong positive correlations were found between copepod density and DO (r = 0.65) and temperature (r = 0.36). In Lambajon, positive correlations existed between water depth and copepod density (r = 0.20). Both sites exhibit low copepod diversity overall, potentially due to anthropogenic pressures. These findings emphasize the need for further research to understand the interactions between environmental factors and copepod diversity, essential for effective conservation and management strategies in these coastal ecosystems.
Davao Research Journal, 2022
The present study investigated the composition, density, abundance, and diversity of benthic fora... more The present study investigated the composition, density, abundance, and diversity of benthic foraminifera, and their relationship with various physico-chemical parameters such as pH, salinity, temperature, and sediment grain size. Foraminifera were collected from the intertidal zone using sediment cores and extracted from the sediments through sieving. The extracted foraminifera were stained with Rose bengal solution and preserved with buffered formalin. A total of 9,459 individuals of foraminifera were identified, consisting of 39 species classified into four orders, 16 families, and 21 genera. The top three most abundant genera were Calcarina, Baculogypsina, and Amphistegina. The comparison (ANOVA) of the abundance of foraminifera among the six stations revealed highly significant differences (P= 0.000; df= 38). Station 1 exhibited the highest diversity of foraminifera on Pujada Island, as indicated by an H' value of 3.06. Conversely, station 6 displayed the lowest diversity, with an H' value of 1.59. The pH, salinity, and temperature values are all within acceptable limits for seawater. The decreased diversity observed in some stations are attributed by various factors, like site disturbance (accessibility to many tourists and availability of beach resorts) and the variation in sediment grain size composition. The findings suggest that generally, Pujada Island remains an undisturbed coastal area. As a result, this study provides a baseline for future monitoring of the impacts of natural and human-induced activities in the region, thereby recommending the use of foraminiferans as bioindicators for marine health.
Tropical Natural History, 2024
This paper comprehensively reviews polychaete species in the Coral Triangle (CT), documenting 750... more This paper comprehensively reviews polychaete species in the Coral Triangle (CT), documenting 750 species across 60 families. The Philippines stands out for the highest species diversity, reflecting more extensive exploration than in other ecoregions. Limited publications in specific regions result from heightened sampling needs and taxonomic expertise. Nereididae and Syllidae, each constituting 11% of the total, are prominent polychaete families, alongside others like Polynoidae, Terebellidae, Eunicidae, Spionidae, and Sigalionidae. The genus Syllis is the most speciose, contributing 4% to the overall tally. Since 1750, polychaete species and publication numbers in the CT show an upward trend, reaching its peak from 2000 to the present. Increased marine biodiversity awareness, using SCUBA diving and ROVs, and advanced technology for species identification have significantly contributed to the continuous increase in recorded species. Despite these advancements, polychaetes in the CT remain relatively understudied compared to other taxa, underscoring the need for additional focused research on polychaetes within the region.
Davao Research Journal, 2023
Asia is widely recognized for its grouper aquaculture. China (65%), Taiwan (17%), and Indonesia (... more Asia is widely recognized for its grouper aquaculture. China (65%), Taiwan (17%), and Indonesia (11%) together account for 93% of global grouper production. This study recorded 48 species, and 16 hybrids were used in Asian aquaculture. The conservation status of cultured grouper species is 67% least concern, 17% data deficient, 10% vulnerable, and 2% critically endangered, endangered, and near threatened. Most Asian countries face issues such as (1) lack of hatcheries, (2) poor seed stock, (3) poor broodstock quality, (4) lack of financial and technical support, (5) trash fish and accessibility to fish pellets, (6) poor water quality, (7) diseases, and (8) capture-based aquaculture. These issues, combined with overfishing, contribute to a decline in grouper productivity and their wild population. The decline has alarmed experts and conservationists looking into the causes and potential remedies to this problem. Some management strategies mentioned in this paper include: (1) closed season during spawning aggregation, (2) establishing more marine protected areas (MPAs), particularly the no-take marine reserve, (3) non-consumptive utilization of groupers (eco-tourism) and (4) establishing more full-cycle grouper aquaculture. The results of this study suggest that implementing these strategies could be an effective means of addressing the issue of grouper production and that additional research is required to determine the most effective method of addressing this problem. The findings of this study have significant implications for the development and sustainability of grouper aquaculture and highlight the need for further research in this area.
Davao research journal, May 8, 2024
Copepods are essential components of marine ecosystems, facilitating energy transfer within these... more Copepods are essential components of marine ecosystems, facilitating energy transfer within these complex systems. The study investigates copepod diversity and distribution in Ban-ao and Lambajon coastal areas in Baganga, Davao Oriental, highlighting the environmental factors influencing copepod populations. Four copepod families representing different orders were identified, with Harpacticoida, Calanoida, and Cyclopoida prevalent in both sites, while Misophrioida was exclusive to Lambajon. Physico-chemical parameters such as dissolved oxygen (DO), pH, salinity, sediment composition, water depth, and temperature were analyzed to understand their correlation with copepod density. The study reveals variations in copepod density and abundance between the sites, with Lambajon showing a higher total density (49 ind/cm³) compared to Ban-ao (35 ind/cm³). The Pearson correlation matrix illustrates complex relationships between copepod density and environmental parameters in each site. In Ban-ao, strong positive correlations were found between copepod density and DO (r = 0.65) and temperature (r = 0.36). In Lambajon, positive correlations existed between water depth and copepod density (r = 0.20). Both sites exhibit low copepod diversity overall, potentially due to anthropogenic pressures. These findings emphasize the need for further research to understand the interactions between environmental factors and copepod diversity, essential for effective conservation and management strategies in these coastal ecosystems.
Davao Research Journal
Asia is widely recognized for its grouper aquaculture. China (65%), Taiwan (17%), and Indonesia (... more Asia is widely recognized for its grouper aquaculture. China (65%), Taiwan (17%), and Indonesia (11%) together account for 93% of global grouper production. This study recorded 48 species, and 16 hybrids were used in Asian aquaculture. The conservation status of cultured grouper species is 67% least concern, 17% data deficient, 10% vulnerable, and 2% critically endangered, endangered, and near threatened. Most Asian countries face issues such as (1) lack of hatcheries, (2) poor seed stock, (3) poor broodstock quality, (4) lack of financial and technical support, (5) trash fish and accessibility to fish pellets, (6) poor water quality, (7) diseases, and (8) capture-based aquaculture. These issues, combined with overfishing, contribute to a decline in grouper productivity and their wild population. The decline has alarmed experts and conservationists looking into the causes and potential remedies to this problem. Some management strategies mentioned in this paper include: (1) closed s...
Davao Research Journal
The present study investigated the composition, density, abundance, and diversity of benthic fora... more The present study investigated the composition, density, abundance, and diversity of benthic foraminifera, and their relationship with various physico-chemical parameters such as pH, salinity, temperature, and sediment grain size. Foraminifera were collected from the intertidal zone using sediment cores and extracted from the sediments through sieving. The extracted foraminifera were stained with Rose bengal solution and preserved with buffered formalin. A total of 9,459 individuals of foraminifera were identified, consisting of 39 species classified into four orders, 16 families, and 21 genera. The top three most abundant genera were Calcarina, Baculogypsina, and Amphistegina. The comparison (ANOVA) of the abundance of foraminifera among the six stations revealed highly significant differences (P= 0.000; df= 38). Station 1 exhibited the highest diversity of foraminifera on Pujada Island, as indicated by an H’ value of 3.06. Conversely, station 6 displayed the lowest diversity, with...
Biodiversitas, 2024
This study explores the meiofaunal communities within Pujada Bay's intertidal zone, Philippines, ... more This study explores the meiofaunal communities within Pujada Bay's intertidal zone, Philippines, meticulously recording 18,193 individuals across 18 taxa. Differences in composition and abundance across sites were observed, with conservation efforts at Guang-guang yielding higher densities (4,613 ind/10 cm-2) compared to less-managed sites such as Magsaysay (928 ind/10 cm-2) and Badas (1,438 ind/10 cm-2). Furthermore, Macambol, distant from direct threats, exhibited notable densities (4,483 ind/10 cm-2), indicating the importance of geographic isolation in ecosystem preservation. Dominant taxa include Nematoda (41%), Copepoda (28%), Foraminifera (22%), and Polychaeta (5%), underscoring their ecological significance in Pujada Bay's meiofaunal community. These findings highlight the efficacy of conservation measures in fostering resilient meiofaunal communities, where management strategies and geographic location play vital roles in biodiversity preservation. This rese arch offers valuable insights into the ecological dynamics of Pujada Bay, emphasizing the indispensable role of conservation in maintaining biodiversity. By elucidating meiofaunal dynamics, this study advances our understanding of the local marine ecosystem and lays the groundwork for broader discussions on marine conservation strategies. Pujada Bay, considered one of the most beautiful bays i n the world, exemplifies the delicate balance between human activities and the imperative of preserving biodiversity in marine environments.
Davao Research Journal, 2024
Copepods are essential components of marine ecosystems, facilitating energy transfer within these... more Copepods are essential components of marine ecosystems, facilitating energy transfer within these complex systems. The study investigates copepod diversity and distribution in Ban-ao and Lambajon coastal areas in Baganga, Davao Oriental, highlighting the environmental factors influencing copepod populations. Four copepod families representing different orders were identified, with Harpacticoida, Calanoida, and Cyclopoida prevalent in both sites, while Misophrioida was exclusive to Lambajon. Physico-chemical parameters such as dissolved oxygen (DO), pH, salinity, sediment composition, water depth, and temperature were analyzed to understand their correlation with copepod density. The study reveals variations in copepod density and abundance between the sites, with Lambajon showing a higher total density (49 ind/cm³) compared to Ban-ao (35 ind/cm³). The Pearson correlation matrix illustrates complex relationships between copepod density and environmental parameters in each site. In Ban-ao, strong positive correlations were found between copepod density and DO (r = 0.65) and temperature (r = 0.36). In Lambajon, positive correlations existed between water depth and copepod density (r = 0.20). Both sites exhibit low copepod diversity overall, potentially due to anthropogenic pressures. These findings emphasize the need for further research to understand the interactions between environmental factors and copepod diversity, essential for effective conservation and management strategies in these coastal ecosystems.
Davao Research Journal, 2022
The present study investigated the composition, density, abundance, and diversity of benthic fora... more The present study investigated the composition, density, abundance, and diversity of benthic foraminifera, and their relationship with various physico-chemical parameters such as pH, salinity, temperature, and sediment grain size. Foraminifera were collected from the intertidal zone using sediment cores and extracted from the sediments through sieving. The extracted foraminifera were stained with Rose bengal solution and preserved with buffered formalin. A total of 9,459 individuals of foraminifera were identified, consisting of 39 species classified into four orders, 16 families, and 21 genera. The top three most abundant genera were Calcarina, Baculogypsina, and Amphistegina. The comparison (ANOVA) of the abundance of foraminifera among the six stations revealed highly significant differences (P= 0.000; df= 38). Station 1 exhibited the highest diversity of foraminifera on Pujada Island, as indicated by an H' value of 3.06. Conversely, station 6 displayed the lowest diversity, with an H' value of 1.59. The pH, salinity, and temperature values are all within acceptable limits for seawater. The decreased diversity observed in some stations are attributed by various factors, like site disturbance (accessibility to many tourists and availability of beach resorts) and the variation in sediment grain size composition. The findings suggest that generally, Pujada Island remains an undisturbed coastal area. As a result, this study provides a baseline for future monitoring of the impacts of natural and human-induced activities in the region, thereby recommending the use of foraminiferans as bioindicators for marine health.
Tropical Natural History, 2024
This paper comprehensively reviews polychaete species in the Coral Triangle (CT), documenting 750... more This paper comprehensively reviews polychaete species in the Coral Triangle (CT), documenting 750 species across 60 families. The Philippines stands out for the highest species diversity, reflecting more extensive exploration than in other ecoregions. Limited publications in specific regions result from heightened sampling needs and taxonomic expertise. Nereididae and Syllidae, each constituting 11% of the total, are prominent polychaete families, alongside others like Polynoidae, Terebellidae, Eunicidae, Spionidae, and Sigalionidae. The genus Syllis is the most speciose, contributing 4% to the overall tally. Since 1750, polychaete species and publication numbers in the CT show an upward trend, reaching its peak from 2000 to the present. Increased marine biodiversity awareness, using SCUBA diving and ROVs, and advanced technology for species identification have significantly contributed to the continuous increase in recorded species. Despite these advancements, polychaetes in the CT remain relatively understudied compared to other taxa, underscoring the need for additional focused research on polychaetes within the region.
Davao Research Journal, 2023
Asia is widely recognized for its grouper aquaculture. China (65%), Taiwan (17%), and Indonesia (... more Asia is widely recognized for its grouper aquaculture. China (65%), Taiwan (17%), and Indonesia (11%) together account for 93% of global grouper production. This study recorded 48 species, and 16 hybrids were used in Asian aquaculture. The conservation status of cultured grouper species is 67% least concern, 17% data deficient, 10% vulnerable, and 2% critically endangered, endangered, and near threatened. Most Asian countries face issues such as (1) lack of hatcheries, (2) poor seed stock, (3) poor broodstock quality, (4) lack of financial and technical support, (5) trash fish and accessibility to fish pellets, (6) poor water quality, (7) diseases, and (8) capture-based aquaculture. These issues, combined with overfishing, contribute to a decline in grouper productivity and their wild population. The decline has alarmed experts and conservationists looking into the causes and potential remedies to this problem. Some management strategies mentioned in this paper include: (1) closed season during spawning aggregation, (2) establishing more marine protected areas (MPAs), particularly the no-take marine reserve, (3) non-consumptive utilization of groupers (eco-tourism) and (4) establishing more full-cycle grouper aquaculture. The results of this study suggest that implementing these strategies could be an effective means of addressing the issue of grouper production and that additional research is required to determine the most effective method of addressing this problem. The findings of this study have significant implications for the development and sustainability of grouper aquaculture and highlight the need for further research in this area.