Abstract: Sida fallax Walp. (‘ilima) (Malveae, Malvoideae, Malvaceae) is native to the Pacific area and is broadly distributed throughout this region. Sida fallax is the most widespread and variable taxon of Malvaceae in the Hawaiian Islands and it occurs with diverse morphological forms and in different habitats from Hawai‘i Island to Midway Atoll. The low elevation and mountain ecotypes are two extreme ecological forms of S. fallax with many intermediate morphological types existing between these extreme ecotypes in the Hawaiian Islands. The range of morphological and ecological diversity in Sida fallax suggests that this species requires further biosystematics investigation. The purpose of this study was two-fold. First, explore the genetic diversity among S. fallax populations throughout its native range in the Pacific region to assess if it is a single species or potentially multiple cryptic species; second, investigate the biogeographic origin of S. fallax. To do this, Sida fallax was sampled throughout the Hawaiian Islands and in different parts of the Pacific region. Bayesian phylogenetic analyses based on nuclear (ITS and ETS) and chloroplast regions (psbA–trnH) were carried out. Results indicate that there is very little sequence-level variation in this species throughout its distribution and phylogenetic analysis clearly demonstrated that Sida fallax is a single species throughout the Pacific region and the different forms of Hawaiian S. fallax are not genetically distinct at the sequence level. Although the pattern of dispersal of S. fallax is not clear, an American origin is most likely.
{"title":"Low Genetic Diversity in the Highly Morphologically Diverse Sida fallax Walp. (Malvaceae) Throughout the Pacific","authors":"Mersedeh Pejhanmehr, Mitsuko Yorkston, C. Morden","doi":"10.2984/76.4.2","DOIUrl":"https://doi.org/10.2984/76.4.2","url":null,"abstract":"Abstract: Sida fallax Walp. (‘ilima) (Malveae, Malvoideae, Malvaceae) is native to the Pacific area and is broadly distributed throughout this region. Sida fallax is the most widespread and variable taxon of Malvaceae in the Hawaiian Islands and it occurs with diverse morphological forms and in different habitats from Hawai‘i Island to Midway Atoll. The low elevation and mountain ecotypes are two extreme ecological forms of S. fallax with many intermediate morphological types existing between these extreme ecotypes in the Hawaiian Islands. The range of morphological and ecological diversity in Sida fallax suggests that this species requires further biosystematics investigation. The purpose of this study was two-fold. First, explore the genetic diversity among S. fallax populations throughout its native range in the Pacific region to assess if it is a single species or potentially multiple cryptic species; second, investigate the biogeographic origin of S. fallax. To do this, Sida fallax was sampled throughout the Hawaiian Islands and in different parts of the Pacific region. Bayesian phylogenetic analyses based on nuclear (ITS and ETS) and chloroplast regions (psbA–trnH) were carried out. Results indicate that there is very little sequence-level variation in this species throughout its distribution and phylogenetic analysis clearly demonstrated that Sida fallax is a single species throughout the Pacific region and the different forms of Hawaiian S. fallax are not genetically distinct at the sequence level. Although the pattern of dispersal of S. fallax is not clear, an American origin is most likely.","PeriodicalId":54650,"journal":{"name":"Pacific Science","volume":"76 1","pages":"361 - 376"},"PeriodicalIF":0.7,"publicationDate":"2023-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48303898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract: I present data on the Mariana Crow for an extensive but previously unavailable set of population and habitat surveys from 1992 to 1993. From these, I (1) compute a series of population estimates from that period during which Mariana Crow numbers were first entering a precipitous decline, (2) quantitatively assess the habitats occupied by individual birds and thereby provide a view of the range of habitats occupied during a time when the species was still widespread, and (3) provide the first direct wet-dry season comparisons of populations and habitat occupancy. Surveys yielded significantly different wet (943) and dry season (459) population estimates, which suggested wet season courtship activity preceding dry season nesting when birds became more secretive. Moreover, they indicated that the critical turning point in population decline was after 1995. Forest was the principal habitat type occupied during both wet and dry seasons, with savanna present less than half as often as forest, although birds occupied a range of additional habitats. The species was more versatile in habitat use than is often assumed, as rates of habitat occupancy and availability were similar. Versatility is an advantage for populations confined to small islands that periodically suffer catastrophic habitat damage due to typhoons.
{"title":"Population Size and Habitat Occupancy by the Endangered Mariana Crow","authors":"R. J. Craig","doi":"10.2984/76.4.1","DOIUrl":"https://doi.org/10.2984/76.4.1","url":null,"abstract":"Abstract: I present data on the Mariana Crow for an extensive but previously unavailable set of population and habitat surveys from 1992 to 1993. From these, I (1) compute a series of population estimates from that period during which Mariana Crow numbers were first entering a precipitous decline, (2) quantitatively assess the habitats occupied by individual birds and thereby provide a view of the range of habitats occupied during a time when the species was still widespread, and (3) provide the first direct wet-dry season comparisons of populations and habitat occupancy. Surveys yielded significantly different wet (943) and dry season (459) population estimates, which suggested wet season courtship activity preceding dry season nesting when birds became more secretive. Moreover, they indicated that the critical turning point in population decline was after 1995. Forest was the principal habitat type occupied during both wet and dry seasons, with savanna present less than half as often as forest, although birds occupied a range of additional habitats. The species was more versatile in habitat use than is often assumed, as rates of habitat occupancy and availability were similar. Versatility is an advantage for populations confined to small islands that periodically suffer catastrophic habitat damage due to typhoons.","PeriodicalId":54650,"journal":{"name":"Pacific Science","volume":"76 1","pages":"349 - 359"},"PeriodicalIF":0.7,"publicationDate":"2023-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48720176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fernando Isea-León, Juan Diego Quispe, Alexandra E. Bermúdez‐Medranda, V. Acosta, A. M. Santana-Piñeros, Y. Cruz‐Quintana, L. M. Soto, Luciana Gomes-Barbosa, L. Dominguez-Granda, C. López
Abstract: This is the first report of plastics ingestion by the neotropical fish Dormitator latifrons. The stomach contents of 20 specimens (10 males and 10 females) collected in La Segua wetland (Ecuador) were assessed visually. Frequency of occurrence (FO) of plastics was 50% and the plastic load (PL) was between 5 and 55 particles per individual. Ninety-seven percent of plastic particles found were microplastics (<5.0 mm), and 3% were larger. No significant differences were found in PL between females and males (>0.05). No significant correlation was found between fish size and PL (>0.05). Fibers were the most frequently observed category, and transparent and blue colors were the most abundant. The results suggest high levels of plastic pollution in waters of La Segua wetland that may represent a threat to both the ecosystem and the people who rely on it.
{"title":"Ingestion of Plastics in a Wild Population of the Pacific Fat Sleeper (Dormitator latifrons)","authors":"Fernando Isea-León, Juan Diego Quispe, Alexandra E. Bermúdez‐Medranda, V. Acosta, A. M. Santana-Piñeros, Y. Cruz‐Quintana, L. M. Soto, Luciana Gomes-Barbosa, L. Dominguez-Granda, C. López","doi":"10.2984/76.4.3","DOIUrl":"https://doi.org/10.2984/76.4.3","url":null,"abstract":"Abstract: This is the first report of plastics ingestion by the neotropical fish Dormitator latifrons. The stomach contents of 20 specimens (10 males and 10 females) collected in La Segua wetland (Ecuador) were assessed visually. Frequency of occurrence (FO) of plastics was 50% and the plastic load (PL) was between 5 and 55 particles per individual. Ninety-seven percent of plastic particles found were microplastics (<5.0 mm), and 3% were larger. No significant differences were found in PL between females and males (>0.05). No significant correlation was found between fish size and PL (>0.05). Fibers were the most frequently observed category, and transparent and blue colors were the most abundant. The results suggest high levels of plastic pollution in waters of La Segua wetland that may represent a threat to both the ecosystem and the people who rely on it.","PeriodicalId":54650,"journal":{"name":"Pacific Science","volume":"76 1","pages":"377 - 383"},"PeriodicalIF":0.7,"publicationDate":"2023-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46333383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. McCullough, L. Decicco, Mark W. Herr, Piokera S. Holland, D. Pikacha, T. Lavery, K. V. Olson, D. A. DeRaad, Ikuo G. Tigulu, X. M. Mapel, Luke B. Klicka, Roy Famoo, Jonathan Hobete, Lazarus Runi, Gloria Rusa, A. Tippet, D. Boseto, Rafe M. Brown, R. Moyle, Michael J. Andersen
Abstract: The Solomon Islands host a diverse terrestrial vertebrate fauna which has played a formative role in the development of speciation theory. Yet, despite over a century of biological exploration in the region, there are many islands for which we have incomplete knowledge of the vertebrate fauna. In 2019, we spent 20 days on Tetepare Island in the Western Province, Solomon Islands. Tetepare has a long history of conservation action by local communities and it is now the largest uninhabited tropical island in the world. We recorded 57 species of birds, 13 mammals, 5 amphibians, and 21 reptiles. Of these, we documented six species for the first time on Tetepare by western scientists: one frog, three non-avian reptiles, and two mammals. These findings point to a continued need for basic biological inventory work to inform research, local conservation efforts, and to increase published knowledge of the biodiversity in the Solomon Islands.
{"title":"A Survey of Terrestrial Vertebrates of Tetepare Island, Solomon Islands, Including Six New Island Records","authors":"J. McCullough, L. Decicco, Mark W. Herr, Piokera S. Holland, D. Pikacha, T. Lavery, K. V. Olson, D. A. DeRaad, Ikuo G. Tigulu, X. M. Mapel, Luke B. Klicka, Roy Famoo, Jonathan Hobete, Lazarus Runi, Gloria Rusa, A. Tippet, D. Boseto, Rafe M. Brown, R. Moyle, Michael J. Andersen","doi":"10.2984/76.4.6","DOIUrl":"https://doi.org/10.2984/76.4.6","url":null,"abstract":"Abstract: The Solomon Islands host a diverse terrestrial vertebrate fauna which has played a formative role in the development of speciation theory. Yet, despite over a century of biological exploration in the region, there are many islands for which we have incomplete knowledge of the vertebrate fauna. In 2019, we spent 20 days on Tetepare Island in the Western Province, Solomon Islands. Tetepare has a long history of conservation action by local communities and it is now the largest uninhabited tropical island in the world. We recorded 57 species of birds, 13 mammals, 5 amphibians, and 21 reptiles. Of these, we documented six species for the first time on Tetepare by western scientists: one frog, three non-avian reptiles, and two mammals. These findings point to a continued need for basic biological inventory work to inform research, local conservation efforts, and to increase published knowledge of the biodiversity in the Solomon Islands.","PeriodicalId":54650,"journal":{"name":"Pacific Science","volume":"76 1","pages":"411 - 435"},"PeriodicalIF":0.7,"publicationDate":"2023-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46260397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract: In nesting areas with extreme climatic conditions, such as high temperatures, it is advisable to use mitigation strategies that counteract these negative effects on the hatching success of sea turtle nests. We evaluated the effect of incubation treatment on hatching success and incubation period for olive ridley turtles Lepidochelys olivacea during the 2019 nesting season in Guerrero, Mexico. Three incubation treatments (T1 = shade & freshwater irrigation; T2 = shade, seawater pre-irrigation, sand covered & freshwater irrigated; T3 = shade, seawater pre-irrigation, covered with a plastic lid & freshwater irrigated) were trialed at two different times during the nesting season. One of our goals was to compare the reproductive success of hatchery nests versus in situ nests, however, in situ nests hatching success was zero. We found that treatments had no effect on hatching success or incubation period, but there were differences in proportions of dead and crushed hatchlings. Clutches incubated in the second relocation period had longer incubation times. However, nest relocation periods had no effect on hatching success, dead hatchlings, or the proportion of crushed hatchlings. Our results also showed that the amount of seawater applied to the holes and the rate of irrigation were not lethal for the incubating eggs, but prolonged the incubation period. These results could help to increase our understanding of sea turtle reproductive success and may serve as a baseline to adapt the spatio-temporal conditions of the hatcheries in other areas with similar environmental conditions.
{"title":"Evaluation of Reproductive Success of the Olive Ridley Turtle Lepidochelys olivacea (Testudinata: Cheloniidae) Using Different Incubation Treatments","authors":"J.L. Sandoval-Ramírez, E. Solana‐Arellano","doi":"10.2984/76.4.4","DOIUrl":"https://doi.org/10.2984/76.4.4","url":null,"abstract":"Abstract: In nesting areas with extreme climatic conditions, such as high temperatures, it is advisable to use mitigation strategies that counteract these negative effects on the hatching success of sea turtle nests. We evaluated the effect of incubation treatment on hatching success and incubation period for olive ridley turtles Lepidochelys olivacea during the 2019 nesting season in Guerrero, Mexico. Three incubation treatments (T1 = shade & freshwater irrigation; T2 = shade, seawater pre-irrigation, sand covered & freshwater irrigated; T3 = shade, seawater pre-irrigation, covered with a plastic lid & freshwater irrigated) were trialed at two different times during the nesting season. One of our goals was to compare the reproductive success of hatchery nests versus in situ nests, however, in situ nests hatching success was zero. We found that treatments had no effect on hatching success or incubation period, but there were differences in proportions of dead and crushed hatchlings. Clutches incubated in the second relocation period had longer incubation times. However, nest relocation periods had no effect on hatching success, dead hatchlings, or the proportion of crushed hatchlings. Our results also showed that the amount of seawater applied to the holes and the rate of irrigation were not lethal for the incubating eggs, but prolonged the incubation period. These results could help to increase our understanding of sea turtle reproductive success and may serve as a baseline to adapt the spatio-temporal conditions of the hatcheries in other areas with similar environmental conditions.","PeriodicalId":54650,"journal":{"name":"Pacific Science","volume":"76 1","pages":"385 - 396"},"PeriodicalIF":0.7,"publicationDate":"2023-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45705538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ariadna Ávila-García, C. Sánchez, Leonardo Huato-Soberanis, E. Borda, J. Gómez‐Gutiérrez
Abstract: Sandyella tricornuta (Hendrickx, 1990) is a small (<13 mm total length), obligate and highly specific ectosymbiont of the black coral Antipathes galapagensis Deichmann, 1941 with a remarkable morphology and body coloration that resembles black coral polyps. Sandyella tricornuta population structure was investigated to infer the reproductive periods evidenced with ovigerous females from monthly collection at Espíritu Santo Island (April 2009–March 2010) and along a latitudinal gradient of six islands (24–30° N, July 2009) located along the west coast of the Gulf of California, Mexico. A total of 2,899 S. tricornuta individuals were collected from 70 colonies of A. galapagensis with a mean density of 210 inds./m3 per black coral colony. Sea floor temperature of S. tricornuta/A. galapagensis habitat seasonally ranged between 21 and 30°C. Females constituted >60% of the entire S. tricornuta population and >59% of the collected females were ovigerous females, suggesting active reproduction throughout the year and along the latitudinal gradient investigated. Sandyella tricornuta population density and sex ratio was similar throughout the year indicating a seasonally stable population size. Total abundance of S. tricornuta was density independent of black coral colony size and weight indicating that S. tricornuta depends on A. galapagensis, but the black coral colony can grow and develop without S. tricornuta characteristic of a commensalism ectosymbiotic association.
{"title":"Continuous Reproduction Causes Stable Population Structure of Antipatharian-Associated Shrimp Sandyella tricornuta (Decapoda: Palaemonidae)","authors":"Ariadna Ávila-García, C. Sánchez, Leonardo Huato-Soberanis, E. Borda, J. Gómez‐Gutiérrez","doi":"10.2984/76.4.5","DOIUrl":"https://doi.org/10.2984/76.4.5","url":null,"abstract":"Abstract: Sandyella tricornuta (Hendrickx, 1990) is a small (<13 mm total length), obligate and highly specific ectosymbiont of the black coral Antipathes galapagensis Deichmann, 1941 with a remarkable morphology and body coloration that resembles black coral polyps. Sandyella tricornuta population structure was investigated to infer the reproductive periods evidenced with ovigerous females from monthly collection at Espíritu Santo Island (April 2009–March 2010) and along a latitudinal gradient of six islands (24–30° N, July 2009) located along the west coast of the Gulf of California, Mexico. A total of 2,899 S. tricornuta individuals were collected from 70 colonies of A. galapagensis with a mean density of 210 inds./m3 per black coral colony. Sea floor temperature of S. tricornuta/A. galapagensis habitat seasonally ranged between 21 and 30°C. Females constituted >60% of the entire S. tricornuta population and >59% of the collected females were ovigerous females, suggesting active reproduction throughout the year and along the latitudinal gradient investigated. Sandyella tricornuta population density and sex ratio was similar throughout the year indicating a seasonally stable population size. Total abundance of S. tricornuta was density independent of black coral colony size and weight indicating that S. tricornuta depends on A. galapagensis, but the black coral colony can grow and develop without S. tricornuta characteristic of a commensalism ectosymbiotic association.","PeriodicalId":54650,"journal":{"name":"Pacific Science","volume":"76 1","pages":"397 - 410"},"PeriodicalIF":0.7,"publicationDate":"2023-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49020817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N. Fernandez, K. Paxton, E. Paxton, A. Pack, P. Hart
Abstract: Acoustic communication in the form of songs is a learned behavior in oscine that can be passed down from one generation to the next through cultural transmission. Over time songs can change when populations become isolated from one another, creating dialects that are distinct to a population. Habitat fragmentation is an isolating mechanism that can influence differences in songs between populations when there is little to no connectivity between fragments and fragment size can influence diversity of song traits. We characterized and analyzed songs of the ‘ōma‘o (Myadestes obscurus) in a naturally fragmented forest to determine how landscape variables influenced song differences between populations. We chose five fragments of different sizes and isolation to record songs of the ‘ōma‘o. We performed a correlation test to evaluate whether there was a relationship between fragment size and total syllables, and between unique syllables and degree of isolation. We also conducted a Mantel test to determine if geographic distance had an influence on song similarity. Our results indicated that songs from larger fragments tended to have higher syllable diversity, but neither connectivity nor distance was related to the number of unique or shared syllables found within a fragment, respectively. Overall, the results indicated that ‘ōma‘o songs are highly variable at the individual level and that there may be little to no syllable sharing within and among populations.
{"title":"Landscape Configuration Influences ‘Ōma‘o (Myadestes obscurus) Song Diversity","authors":"N. Fernandez, K. Paxton, E. Paxton, A. Pack, P. Hart","doi":"10.2984/76.3.6","DOIUrl":"https://doi.org/10.2984/76.3.6","url":null,"abstract":"Abstract: Acoustic communication in the form of songs is a learned behavior in oscine that can be passed down from one generation to the next through cultural transmission. Over time songs can change when populations become isolated from one another, creating dialects that are distinct to a population. Habitat fragmentation is an isolating mechanism that can influence differences in songs between populations when there is little to no connectivity between fragments and fragment size can influence diversity of song traits. We characterized and analyzed songs of the ‘ōma‘o (Myadestes obscurus) in a naturally fragmented forest to determine how landscape variables influenced song differences between populations. We chose five fragments of different sizes and isolation to record songs of the ‘ōma‘o. We performed a correlation test to evaluate whether there was a relationship between fragment size and total syllables, and between unique syllables and degree of isolation. We also conducted a Mantel test to determine if geographic distance had an influence on song similarity. Our results indicated that songs from larger fragments tended to have higher syllable diversity, but neither connectivity nor distance was related to the number of unique or shared syllables found within a fragment, respectively. Overall, the results indicated that ‘ōma‘o songs are highly variable at the individual level and that there may be little to no syllable sharing within and among populations.","PeriodicalId":54650,"journal":{"name":"Pacific Science","volume":"76 1","pages":"325 - 335"},"PeriodicalIF":0.7,"publicationDate":"2023-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44951677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract: The U.S. Tropical Pacific (USTP) is a globally important area for seabirds with tens of millions of individuals of 32 species breeding in the region. The two greatest threats to breeding seabirds in the USTP are inundation of colonies caused by global climate change and non-native predators. We assessed the status of seabird species breeding in the USTP and which species would benefit most from restoration activities. We scored each species for nine criteria that reflected their extinction risk and vulnerability to climate change and invasive predators, then summed the scores of all criteria to obtain an overall score and ranked the species in terms of overall conservation need. The top five species at risk (in order) were Hawaiian Petrel (Pterodroma sandwichensis), Newell's Shearwater (Puffinus newelli), Polynesian Storm-Petrel (Nesofregetta fuliginosa), Phoenix Petrel (Pterodroma alba), and Black-footed Albatross (Phoebastria nigripes). We also assessed 86 locations in the USTP as potential source and restoration sites for seabirds to mitigate the impacts of sea level rise and invasive predators. Some restoration actions are underway for three of the top five species in the USTP, but more actions are needed. Two of the top species (Polynesian Storm-petrel and Phoenix Petrel) occur primarily outside the USTP. Actions within the USTP are needed to complement existing conservation measures underway elsewhere in the Pacific and should be prioritized for future management actions.
{"title":"Prioritization of Restoration Needs for Seabirds in the U.S. Tropical Pacific Vulnerable to Climate Change","authors":"L. Young, E. VanderWerf","doi":"10.2984/76.3.1","DOIUrl":"https://doi.org/10.2984/76.3.1","url":null,"abstract":"Abstract: The U.S. Tropical Pacific (USTP) is a globally important area for seabirds with tens of millions of individuals of 32 species breeding in the region. The two greatest threats to breeding seabirds in the USTP are inundation of colonies caused by global climate change and non-native predators. We assessed the status of seabird species breeding in the USTP and which species would benefit most from restoration activities. We scored each species for nine criteria that reflected their extinction risk and vulnerability to climate change and invasive predators, then summed the scores of all criteria to obtain an overall score and ranked the species in terms of overall conservation need. The top five species at risk (in order) were Hawaiian Petrel (Pterodroma sandwichensis), Newell's Shearwater (Puffinus newelli), Polynesian Storm-Petrel (Nesofregetta fuliginosa), Phoenix Petrel (Pterodroma alba), and Black-footed Albatross (Phoebastria nigripes). We also assessed 86 locations in the USTP as potential source and restoration sites for seabirds to mitigate the impacts of sea level rise and invasive predators. Some restoration actions are underway for three of the top five species in the USTP, but more actions are needed. Two of the top species (Polynesian Storm-petrel and Phoenix Petrel) occur primarily outside the USTP. Actions within the USTP are needed to complement existing conservation measures underway elsewhere in the Pacific and should be prioritized for future management actions.","PeriodicalId":54650,"journal":{"name":"Pacific Science","volume":"76 1","pages":"247 - 265"},"PeriodicalIF":0.7,"publicationDate":"2023-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46161292","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract: Few ponds are found in the permeable volcanic landscape of Hawaii. After Hurricane Lane passed close to Hawaii Island in August 2018, causing record rainfalls, a pond temporarily emerged on the Mauna Kea summit plateau that had never been reported before. We characterize the pond using satellite observations and electrical resistivity tomography. The shallow pond is located on glacial till 3,594 m a.s.l., and was visible for less than 1 week. The geophysical survey, carried out 10 months after the pond's appearance and disappearance, revealed a layer of low electrical resistivity at depths of about 1–3 m below the surface, which, based on laboratory analysis, likely represents a perennial body of water well protected from evaporation. The existence of a third pond, in addition to Lake Waiau and Pu‘upōhaku Pond, in the previously glaciated area suggests perching layers are not uncommon. Montmorillonite, a 3-layer shrink-swell clay that can help to perch water, was identified in the Lake Waiau area. Mineral analysis on surface samples of the third pond did not reveal such a clay mineral.
{"title":"A Third Pond on the Mauna Kea Summit Plateau","authors":"N. Schorghofer, M. Leopold, F. Klasner","doi":"10.2984/76.3.3","DOIUrl":"https://doi.org/10.2984/76.3.3","url":null,"abstract":"Abstract: Few ponds are found in the permeable volcanic landscape of Hawaii. After Hurricane Lane passed close to Hawaii Island in August 2018, causing record rainfalls, a pond temporarily emerged on the Mauna Kea summit plateau that had never been reported before. We characterize the pond using satellite observations and electrical resistivity tomography. The shallow pond is located on glacial till 3,594 m a.s.l., and was visible for less than 1 week. The geophysical survey, carried out 10 months after the pond's appearance and disappearance, revealed a layer of low electrical resistivity at depths of about 1–3 m below the surface, which, based on laboratory analysis, likely represents a perennial body of water well protected from evaporation. The existence of a third pond, in addition to Lake Waiau and Pu‘upōhaku Pond, in the previously glaciated area suggests perching layers are not uncommon. Montmorillonite, a 3-layer shrink-swell clay that can help to perch water, was identified in the Lake Waiau area. Mineral analysis on surface samples of the third pond did not reveal such a clay mineral.","PeriodicalId":54650,"journal":{"name":"Pacific Science","volume":"76 1","pages":"277 - 287"},"PeriodicalIF":0.7,"publicationDate":"2023-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43112762","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract: Lake Tagimaucia, a montane volcanic lake on Taveuni Island, is Fiji's only high-elevation lake. This study examined a lacustrine sediment core to explore the lake's potential as a palaeoenvironmental archive through the Late Holocene. Dating reveals no simple age–depth relationship due to sediment age-reversals. However, phases of fire activity are evidenced by two distinct charcoal bands. Catchment burns were probably related to significant ENSO-driven drought, although fire ignition by volcanic eruptions on Taveuni cannot be ruled out. Above the dominant charcoal band, the sediment profile exhibits notable positive shifts in organic matter, bulk density, δ13C, and C:N ratio. These peaks suggest a phase of accelerated catchment erosion, possibly triggered by post-burn instability. We introduce a conceptual model to explain the influence of sedge peat swamps on lake sedimentation processes. Surrounding sedge-dominated peatlands have extensively encroached Lake Tagimaucia. Floating peat mats, gradually accumulating through time, act as a repository of organic material that is stored directly on the lake surface. Episodes of drought and fire release old organics directly into the lake itself, probably contributing to the complex chronological sequence in the Late Holocene stratigraphy.
{"title":"Lake Tagimaucia Montane Lake as a Potential Late Holocene Environmental Archive in Fiji's Volcanic Highlands","authors":"J. Terry, Kunal Singh, M. McKeown","doi":"10.2984/76.3.4","DOIUrl":"https://doi.org/10.2984/76.3.4","url":null,"abstract":"Abstract: Lake Tagimaucia, a montane volcanic lake on Taveuni Island, is Fiji's only high-elevation lake. This study examined a lacustrine sediment core to explore the lake's potential as a palaeoenvironmental archive through the Late Holocene. Dating reveals no simple age–depth relationship due to sediment age-reversals. However, phases of fire activity are evidenced by two distinct charcoal bands. Catchment burns were probably related to significant ENSO-driven drought, although fire ignition by volcanic eruptions on Taveuni cannot be ruled out. Above the dominant charcoal band, the sediment profile exhibits notable positive shifts in organic matter, bulk density, δ13C, and C:N ratio. These peaks suggest a phase of accelerated catchment erosion, possibly triggered by post-burn instability. We introduce a conceptual model to explain the influence of sedge peat swamps on lake sedimentation processes. Surrounding sedge-dominated peatlands have extensively encroached Lake Tagimaucia. Floating peat mats, gradually accumulating through time, act as a repository of organic material that is stored directly on the lake surface. Episodes of drought and fire release old organics directly into the lake itself, probably contributing to the complex chronological sequence in the Late Holocene stratigraphy.","PeriodicalId":54650,"journal":{"name":"Pacific Science","volume":"76 1","pages":"289 - 311"},"PeriodicalIF":0.7,"publicationDate":"2023-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49440950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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