Progress 01/12/15 to 09/30/18
Outputs
Target Audience: Several groups and entities benefitted from the work supported by my McIntire-Stennis Grant. Government agencies include the US Fish andWildlife Service, Guam Division of Aquatic and Wildlife Resources, US National Park Service, USDA APHIS, andthe Joint Region Marianas(JRM) of the DoD. Non-agency targets include members of the scientific community associated with the University of Guam, some of thegeneral public, including undergraduate and graduate students. Changes/Problems: Predation is difficult to assess on a large scale, though it is possible to find evidence during surveys of large areas. It may be necessary to focus on one location, clearing the ground under trees to accurately assess the number of newly dead snails. Flatworms are generally only active at night, particularly on wet or rainy daysUnfortunately, the location I chose for a detailed predation survey was at leat twice during 2018. The seedless breadfruit trees, the dominant vegetation there and home plant forP. radiolata,were targetted by poachers. Trees were cut, saplings chopped off, and branches broken to harvest the large leaves for some cultural practice. Many of the small trees we were monitoring bearing snails were destroyed or damaged. What opportunities for training and professional development has the project provided?This project has provided several opportunities for training and professional development, primarily to students at the University of Guam and staff of local and federal government agencies, as well as myself. One undergraduate in the UOG Biology program helped with fieldwork, including surveys and GIS work, as part of his directed research project. My graduate student continued her work with tree snails, supported by our new Graduate Assistant Instructor program. These students had an opportunity to learn more about the biology of tree snails, plant identification, field methodology, and limestone forest ecology. These experiences for students are important, as they provided practical training in field research, and exposure to field biology and conservation. Collaborations with various government agencies also provided opportunities for training and personal development. I worked closely with the DoD to provide a visual training presentation to locate identify tree snails for contractors and did a similar session (with field component) for the 2018 Island Forest Ecology Course. These skills will be important for DoD contractors in identifying endangered tree snails while working in forests on DoD installations. We also further developed the idea of a field guide for native tree snails and identified funding from DoD and USFWS that can be used to layout and publish this document in the future. My own professional development was furthered by my attendance of the 2018 joint meeting of American Malacological Society and Western Society of Malacologists in Honolulu, in June. I was able to network with other biologists working with land snails around the Pacific and set up future collaborations. The post conference work with the Malacology collection at the Bishop Museum in Honolulu allowed me to further my interactions with malacologists and examine the collection for partulid snails from the Marianas housed there. How have the results been disseminated to communities of interest?Some of the results of this project and the status of tree snails have been disseminated to the public. I presented a general talk on tree snail conservation at the first Mariana Terrestrial Conservation Conference in November 2017 in Mangilao Guam. In June 2018, I used McIntire-Stennis funding to attend the 2018 joint meeting of American Malacological Society and Western Society of Malacologists in Honolulu, where I presented a talk entitled, "Conservation Status of Guam's Partulid Snails". Although I did not publish any papers in the last year, I have begun drafting manuscripts describing (with photographs) the collection of land snails from the Marianas at the Bishop Museum, in addition to a paper to update the status of populations of tree snails on Guam. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
Overview: This project was undertaken to assess the conservation status of the three species of native tree snails on Guam and in the CNMI. Our efforts in FY2018 focused on defining populations we haven't been able to access previously, analyzing plant use and snail molecular data, and sharing our results with other malacologists at an international meeting, examining a vast museum collection of land snails from this region, mapping a few additional populations of the Guam tree snail (Partula radiolata), and assessing the remaining Guam populations of Partula gibba at Haputoand Samoana fragilis in other locations. These assessments expand the known range of these species, improves our understanding of the status of the rarer species, and helps us make conservation recommendations. Populations P. gibba and S. fragilis may be at increased risk from anthropogenic sources, particularly with private and public development increasing on island. In this final year of the project, five additional populations of the Guam tree snail (Partula radiolata) were identified. Four of these populations could be impacted by construction projects in the near future. Additionally, the population of S. fragilis at Marbo cave discovered last year was found to extend into the construction zone for a solar farm, though overall counts at the entire location were lower than the previous year. The population of S. fragilis at the northern portion of the Haputo Ecological Reserve (Pugua Point) was found to be more extensive that previously known. However, the only Guam population of P. gibba at Haputo Beach in the southern portion of the Haputo Ecological Reserve has plummeted and shifted further south. This suggests both rare and common species are at continued risk. In summary, the third year of the study provided good additional data for the locations of tree snails on Guam, preliminary information on predation and plant use, and established collaborations with various private and public stakeholders in the region. Progress on Objectives 1) ID and Map Partulid Populations a) Conduct surveys on all accessible Mariana islands to locate partulid snails. I verified new populations of P. radiolata found by others or myself while working on other projects and marked these for future assessment. One of these was found on Navy land (NCTS) below a small arms firing range, one in Sinajana along a pipleline project, one in Dededo on public land maintained by the Ayuda Foundation, and two others on or near public land utilized by the Guam Waterworks Authority (Talofofo and Chalan Pago). With access to the Haputo Ecological Reserve Area (HERA) at NCTS for another project, I was able to assess populations of P. gibba and S. fragilis there. Previously, the P. gibba population at Haputo was known mostly from the coastal forest in the southern portion of Haputo Beach, and has been assessed at ~100 individuals as recently as 2014. A lengthy search of the same area in the Spring of 2018 yielded a single P. gibba subadult in the same area. I extended the search to the south of the Haputo basin to the adjacent coastal slope to the south, and located perhaps 100 more P. gibba individuals, where only a few had been previously known. This suggests the only Guam population of P. gibba is at risk and requires extensive monitoring. I also examined the northern portion of HERA, Pugua Point, to assess the population of S. fragilis previously reported there. I found the range of S. fragilis at Pugua Point extended much further northward than previously known, beyond the boundary of the naval base. A detailed count could not be made, but clearly S. fragilis and P. radiolata numbers were much more than 100 individuals. The population of fragile tree snail (S. fragilis) at Marbo Cave discovered last year appears to have decreased to nearly 30 individuals, though several were found in an adjacent plot across the road, in a construction project footprint. b) Assess population sizes of each partulid snail species found. I was not able to reassess most population sizes, with a few exceptions. Counts of S. fragilis were carried out at Marbo, totaling at most 30 individuals. At Lost Pond (Hilaan), several individuals were counted, but haphazard clearing of vegetation around the pond destroyed previously occupied habitat and opened up the canopy. A single count of S. fragilis at Sella Bay yielded only 15 individuals. Comparison of COI sequences from six S. fragilis populations on Guam and the single population on Rota indicate few genetic differences (<1%) between any of the populations. Systematic counts of P. radiolata were not done in this fiscal year. Count of P. gibba at Haputo, yielded ~100 individuals (see above), though population has shifted to the south. c) Accurately map populations using GPS Locations and approximate boundaries (if surveys were possible) of all tree snail populations visited this last year were mapped. 2) Characterize Vegetation I did not carry out this out during this project year. 3) Characterize & Quantify Predation a) Note occurrence of empty shells in different locations. Empty shells of all species were found at nearly every site with extant populations of partulid snails. b) Assess empty shells for evidence of predator damage. Most empty shells lacked physical damage associated with rats or terrestrial crabs. These are consistent with observations of predation by the manokwari flatworm, Platydemus manokwari. c) Record predation events and map presence of known predators. Predation events were fortuitous and were only been observed a few times in the last year. All direct observations of predation have involved P. manokwari, and these flatworms have been observed at nearly all of the locations surveyed. d) Undertake detailed predation surveys at specific sites with high mortality levels. My planned predation survey site at Asan Beach park was vandalized at least twice in the last year, causing me to abandon detailed predation surveys. Saplings and small branches were systematically cut throughout the grove of Lemai (seedless breadfruit) by poachers wanting to harvest the large leaves for some cultural practice.
Publications
- Type:
Conference Papers and Presentations
Status:
Accepted
Year Published:
2017
Citation:
Fiedler, G.C. and A.M. Kerr. 2017. Current Status of Tree Snails in the Marianas. Presentation for the 2017 Mariannas Terrestrial Conservation Conference, Mangilao, Guam.
- Type:
Conference Papers and Presentations
Status:
Accepted
Year Published:
2017
Citation:
Fiedler, G.C. and A.M. Kerr. 2018. Conservation Status of Guams Partulid Snails. 2018 Annual Meeting for American Malacological Society and the Western Society of Malacologists, Honolulu, Hawaii.
|
Progress 10/01/16 to 09/30/17
Outputs
Target Audience:Several groups and entities benefitted from the work supported by my McIntire-Stennis Grant. Government agencies include the US Fish and Wildlife Service, Guam Division of Aquatic and Wildlife Resources, US National Park Service, USDA APHIS,and the Joint RegionMarianas (JRM) of the DoD.Non-agency targets include members of the scientific community associated with the University of Guam, some of the general public, including undergraduate and graduate students. Changes/Problems:Predation is difficult to assess on a large scale, though it is possible to find evidence during surveys of large areas. It may be necessary to focus on one location, clearing the ground under trees to accurately assess the number of newly dead snails. What opportunities for training and professional development has the project provided?This project has provided several opportunities for training and professional development, primarily to students at the University of Guamand staff of local and federal government agencies. Two undergraduates in the UOG Biology program have helped with fieldwork, including surveys and characterization of home plant use by snails. My graduate student continued her work with tree snails, supported by our newGraduate Assistant Program. One student undertook a directed research project focused on helping with snail surveys. Another student, an LSAMP intern, helped map Samoana fragilis at Marbo cave and P. radiolata at other locations. These students had an opportunity to learn more about the biology of tree snails, plant identification, field methodology, and limestone forest ecology. These experiences for students are important, as they provided practical training in field research, and exposure to field biology and conservation. Collaborations with various government agencies also provided opportunities for training and personal development. I worked closely with biological technicians from the National Park Service and Guam's Division of Aquatic and Wildlife Resources. I trained them to locate and identify tree snails, even joining them for survey work. These skills will be important for NPS and DAWR in assessing tree snails at their holdings on Guam and elsewhere, as well as determine the degree of threat by little fire ants (LFA or Wasmannia auropunctata). I also made a quick ID guide for the USDA Aphis team, so that they could better ID native tree snails during their ungulate eradication surveys. I've also developed a visual guide to common land snails with the help of the UOG Cooperative Extension service publication team. We hope to make this available in some format in 2017. How have the results been disseminated to communities of interest?Some of the results of this project and the status of Guam's tree snails have been disseminated to the public. I presented a talk on tree snails at a research conference (ARC) held by UOGs CLASS (College of Liberal Arts and Social Sciences) on campus, and at an international conference on conservation and sustainability put on by UOG's Center for Island Sustainability. I also co-published a paper with Dr. Alex Kerr (UOG Marine Lab) on terrestrial snails of Cocos island: Kerr, A.M. and Fiedler, G.C. (2017). Land Snails of Dåno (Cocos Island), Mariana Islands. Pacific Science, 72(2):1-16. We have other manuscripts prepared for submission in the coming months. What do you plan to do during the next reporting period to accomplish the goals?Focus less on surveys and focus more on targetted data collection on predation and vegetation use.
Impacts
What was accomplished under these goals?
Overview: This project was undertaken to assess the conservation status of the three species of native tree snails on Guam and in the CNMI. Our efforts in FY2017 focused on defining populations, characterizing vegetation use, and predation sources of partulids on Guam. In this third year of the project, several additional populations of the Guam tree snail (Partula radiolata) and one additional population of the very rare fragile tree snail (Samoana fragilis) were identified on Guam. This discovery expands the known range of these species, improves our ability to find additional sites, and helps us make conservation recommendations. Although this expanded the number of known populations of this species, counts of Guam tree snails at most new sites were relatively low. This suggests even the most common and widespread species are at risk. Wherever they did occur, native tree snails could be found on most any plant (both native and exotic). However, they were more likely on broad-leaved plants that either provided canopy or were well shaded by other plants. One of our surveys found that snail height (distance from grown on home trees) was affected more by the particular day they were measured than any other factor. This implied that weather conditions affected what parts of the trees were used by tree snais. We found further evidence of predation on both snail species by the Manokwari flatworm (Platydemus manokwari) at several locations, indicating it is a major threat to native tree snails, island wide. In summary, the third year of the study provided good additional data for the locations of tree snails on Guam, preliminary information on predation and plant use, and established collaborations with various private and public stakeholders in the region. Progress on Objectives 1) ID and Map Partulid Populations a) Conduct surveys on all accessible Mariana islands to locate partulid snails. Several preliminary and detailed surveys were conducted on Guam to locate and characterize populations of native tree snails. Six new populations of Guam tree snail (P. radiolata) were observed in Harmon (near Cost-U-Less), Santa Rita (Guatali River), Agat (Apaca Point Park), Piti (Piti Guns Trail) and Dededo (Andersen Base South), and Nimitz Hill. Other populations were reported to me in Agat (Waste Water Treatment Plant) and one in Santa Rita (Atantano River), and Barrigada, but could not be accessed at this time. One new population of fragile tree snail (S. fragilis) was located in Mangilao, near Marbo Cave. This population is notable as it is the only partulid population known north of Taguan on the eastern side of Guam. Although it is the sixth population of S. fragilis known on Guam, it is the only one that does not co-occur with P. radiolata. A new population of Pythia scarabaeus (not tree snails) was confirmed on Alupat Island, a small islet on the north margin of Hagatña Bay, bringing the known populations to five on Guam. b) Assess population sizes of each partulid snail species found. Guam: Counts of S. fragilis were carried out at Marbo, totaling at most 61 individuals. At Lost Pond (Hilaan), 77 individuals were counted. A single count of S. fragilis at Sella Bay yielded only than 20 individuals. Counts of P. radiolata were made at a few locations, mostly for new populations. Thirty four P. radiolata were on the margin of private property along a road in Harmon. Six individuals were seen in thick Pago at Apaca point in Agat on a meander survey. Approximately 20 snails were seen along the stairway leading to the Piti Guns national park. Counts on other National Park Service holdings in collaboration with NPS personnel were planned, but could not be completed due to schedule conflicts. However, survey methodology was developed for counting tree snails with a sub-meter accuracy GPS unit (Trimble Geo). c) Accurately map populations using GPS Locations and approximate boundaries of all tree snail populations surveyed in the second year were recorded using GPS unit, and preliminary maps have been generated. 2) Characterize Vegetation a) Identify home plants used by snails in each location during above partulid surveys. Home plants used by snails have been identified in all locations, but not yet been quantified. b) Map vegetation patterns Vegetation patterns have been mapped for some surveys. c) Quantify usage patterns Vegetation usage was recorded for many surveys and is being analyzed. 3) Characterize & Quantify Predation a) Note occurrence of empty shells in different locations. At Marbo, during the rainy season in the Summer, Samoana fragilis were particularly hit hard by Platydemus, and it was observed (and photographed) first hand on two different rainy days. Following the first heavy rainstorms of the season, many empty Samoana shells were found on the ground, with no indication of physical damage. This is consistent with predation by Platydemus. b) Assess empty shells for evidence of predator damage. Most empty shells lack physical damage associated with rats or terrestrial crabs. These are consistent with observations of predation by the manokwari flatworm, Platydemus manokwari. c) Record predation events and map presence of known predators. Predation events were fortuitous and were only been observed a few times in the last year. All direct observations of predation have involved P. manokwari, and these flatworms have been observed at nearly all of the locations surveyed. ?d) Undertake detailed predation surveys at specific sites with high mortality levels. Sites for this effort have yet to be determined.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2017
Citation:
Kerr, A.M. and Fiedler, G.C. (2017). Land Snails of D�no (Cocos Island), Mariana Islands. Pacific Science, 72(2):1-16.
- Type:
Journal Articles
Status:
Other
Year Published:
2018
Citation:
Kerr, A.M., C. Dizon & Fiedler, G.C. (In Prep). Land Snails of Alupat Island, Mariana Islands.
- Type:
Conference Papers and Presentations
Status:
Accepted
Year Published:
2017
Citation:
Fiedler, G.C. 2017. Conservation of Guams Tree Snails. Presentation at the 38th Annual Research Conference, College of Liberal Arts & Social Sciences, University of Guam.
- Type:
Conference Papers and Presentations
Status:
Accepted
Year Published:
2017
Citation:
Fiedler, G.C. 2017. Save Our Snails? Presentation for the 8th Island Sustainability Conference, UOG Center for Island Sustainability, Guam.
|
Progress 10/01/15 to 09/30/16
Outputs
Target Audience:Several groups and entities benefitted from the work supported by my McIntire-Stennis Grant. Government agencies include the Department of Defense JRM (Join Region Marianas),US Fish and Wildlife Service, Guam Division of Aquatic and Wildlife Resources, US National Park Service, andthe Commonwealth of Northern Mariana Islands (CNMI) Department of Lands and Natural Resources Division of Fish and Wildlife. Non-agency targets include members of the scientific community associated with the University of Guam, some of the general public, including undergraduate and graduate students. Changes/Problems:Problems with university procurement office has hampered travel requests. Carrying out direct observations of predation may require a different approach than we have used. What opportunities for training and professional development has the project provided?Training & Professional Development Opportunities. This project has provided several opportunities for training and professional development, primarily to students at the University of Guamand staff of local and federal government agencies. At least eight undergraduates in the UOG Biology program have helped with fieldwork, including surveys and the relocation of snails at Taguan. Two students had Louis Stokes minority internships (LSAMP) to work with snails, while others were volunteers that wantedexperience in the field. My graduate student continued her work with tree snails, supported by our newGraduate Assistant Program, and joined the CNMI survey. Two students, including a USFWS intern at the Ritidian Refuge, undertook directed research projects focused on helping with snail surveys. These students had an opportunity to learn more about the biology of tree snails, plant identification, field methodology, and limestone forest ecology. These experiences for students are important, as they provided practical training in field research, and exposure to field biology and conservation. Collaborations with various government agencies also provided opportunities for training and personal development. I worked closely with biological technicians from the National Park Service, and trained them to locate and identify tree snails, even joining them for survey work. These skills will be important for NPS in assessing tree snails at their holdings on Guam and elsewhere. The relocation of the threatened population of P. radiolata at Taguan was a collaborative effort by my lab with USFWS and Guam's DAWR. CNMI's FWS and DLNR provided extraordinary assistance for my team on Saipan and Rota. These interactions were mutually beneficial, and enhanced our shared understanding of the conservation challenges for partulid snails. I've also developed a visual guide to common land snails with the help of the UOG Cooperative Extension service publication team. We hope to make this available in some format in 2017. How have the results been disseminated to communities of interest?Some of the results of this project and the status of Guam's tree snails have been disseminated to the public. I've made several presenations to UOG undergraduates enrolled in our environmental biology courses, as well as the undergraduate Biology club. I committed to a Science Sundaypresentation on tree snails for the National Park Service. I also co-published a paper with Dr. Alex Kerr (UOG Marine Lab) on sinistral populations of P. gibba: Kerr, A.M. and Fiedler, G.C. (2016). Sinistral coiling in the arboreal snail Partula gibba Férussac, 1821 (Stylommatophora: Partulidae) from Guam, Mariana Islands. American Malacological Bulletin, 34(1): 1-5. What do you plan to do during the next reporting period to accomplish the goals?Analyze vegetation use results, compare DNA from populations ofSamoana fraglilison Guam and Rota, identify an easily accessible location to carry out predation observations, publish an updateon populations of partulids from Guam, return to Rota (CNMI) to complete survey of snail populations, conduct snail surveys on two more small offshore islands (from Guam), access snail populations for surveys on DoD land.
Impacts
What was accomplished under these goals?
1) ID and Map Partulid Populations a) Conduct surveys on all accessible Mariana islands to locate partulid snails. Several preliminary and detailed surveys were conducted on Guam to locate and characterize populations of native tree snails. Five new populations of Guam tree snail (P. radiolata) were observed at Taguan (1000 Steps), Asan River, Faifai Beach, San Carlos Falls, and east Ritidian. Two other populations were reported to me in Agat and one in Jinapsen Road, along with photographs and geotags, but could not be accessed. One new population of fragile tree snail (S. fragilis) was located near San Carlos Falls (Lonfit River), sympatric with P. radiolata. Several survey locations yielded no native tree snails including most of east Ritidian, Jinapsen Cave, Cocos Island, and a small island near Oka Point Alupat Isldan. New populations of the Pythia scarabaeus (not tree snails) were confirmed at Faifai Beach and Tanguisson - bringing the known populations to four on Guam. Surveys of tree snails on Saipan and Rota were carried out in late July 2016. The only population of Partula gibba confirmed on Saipan was near Kagman. The population previously reported at American Memorial Park in Garapan could not be confirmed, and is likely extinct due to the previous year's typhoon. No other populations were confirmed, though old weathered, partulid shells were found at other locations, including sinistrally coiled shells. On Rota, five distinct populations of P. gibba were located at Swimming Hole, Tonga Cave, Honey Garden, and Water Cave Pipeline. One population of Samoana fragilis was confirmed along the Water Cave Pipeline. Old weathered shells were observed at a number of locations. b) Assess population sizes of each partulid snail species found. Guam: Monthly counts of S. fragilis were carried out at Hilaan, with population estimates ranging from ~50 to 150 individuals. Two counts of S. fragilis at Sella Bay suggest a population less than 30 individuals. Counts of S. fragilis at San Carlos Falls ranged from 30-100 invividauls on two different surveys. Counts of P. radiolata were made at several locations. In many cases, snails were distributed over a large area and could not all be counted. A meander survey of the western portion of Ritidian yielded 987 individuals, and series of parallel transects conducted with USFWS interns over the entire area showed comparable numbers. Numbers and range were lower than counts on the same transect lines in 2010. Never the less, the actual numbers could be in the thousands. On the eastern side of the refuge, only two individuals 200m apart were found. Meander surveys and counts of P. radiolata ranged from 1193 at Hilaan (160 per person hour) to 6 at the Guam zoo. A new population at Taguan (1000 Steps) in Mangilao was counted and relocated to another habitat (Agana Spring) to avoid damage from frequent brush fires. All 95 individuals were moved, though a few may have been overlooked. Access to Faifai beach was granted and the meander count was nearly 300 (49 per person hour. Saipan: The only population of P. gibba on Saipan was at Kagman, where only 19 individuals were found. Rota: Only 30 Samoana fragilis were found at Water Cave Pipeline. Putative P. gibba ranged from 17 at the above location to 310 at Water Hole. c) Accurately map populations using GPS Locations and approximate boundaries of all tree snail populations surveyed in the second year were recorded using GPS unit, and preliminary maps have been generated. 2) Characterize Vegetation a) Identify home plants used by snails in each location during above partulid surveys. Home plants used by snails have been identified in all locations, but not yet been quantified. b) Map vegetation patterns Vegetation patterns have been mapped for some surveys. c) Quantify usage patterns Vegetation usage was recorded for many surveys and is being analyzed. 3) Characterize & Quantify Predation a) Note occurrence of empty shells in different locations. Empty shells collections at Hilaan, will show S. fragilis shells far outnumber those of P. radiolata, despite the fact that the latter species is much more common in that location. Empty shells of P. gibba (Saipan & Rota) and S. fragilis (Rota) were also collected in the CNMI at all locations with extant partulid populations. b) Assess empty shells for evidence of predator damage. Most empty shells lack physical damage associated with rats or terrestrial crabs, even on Rota and Saipan where rats are relatively common. In some cases, empty shells were found attached partly attached to substrate by remnants of mucus, and some contained morbid snail tissue. These are consistent with observations of predation by the manokwari flatworm, Platydemus manokwari. c) Record predation events and map presence of known predators. Predation events were fortuitous and were only been observed a few times in the last year. All direct observations of predation have involved P. manokwari, and these flatworms have been observed at nearly of the locations surveyed, including the CNMI. d) Undertake detailed predation surveys at specific sites with high mortality levels. Sites for this effort have yet to be determined.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2016
Citation:
Kerr, A.M. and Fiedler, G.C. (2016). Sinistral coiling in the arboreal snail Partula gibba F�russac, 1821 (Stylommatophora: Partulidae) from Guam, Mariana Islands. American Malacological Bulletin, 34(1): 1-5.
- Type:
Journal Articles
Status:
Submitted
Year Published:
2017
Citation:
Kerr, A.M. and Fiedler, G.C. (In Prep). Land Snails of D�no (Cocos Island), Mariana Islands.
|
Progress 01/12/15 to 09/30/15
Outputs
Target Audience:Several groups and entities benefitted from the worksupported by my McIntire-Stennis Grant. Government agenciesinclude theUS Fish and Wildlife Service, Guam Division of Aquatic and Wildlife Resources, US National Park Service, and theCommonwealth of Northern Mariana Islands (CNMI) Department of Lands and Natural Resources Division of Fish and Wildlife. Non-agency targets include members of the scientific community associated withthe University of Guam, some of the general public, including undergraduate and graduate students. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?This project has provided several opportunities for training and professional development, primarily to students at the University of Guamand staff of local and federal government agencies. At least eight undergraduates in the UOG Biology program have helped with fieldwork, including surveys and the relocation of snails at Asan Beach Park. One such student had a Louis Stokes minority internship (LSAMP) to work with snails, while others were volunteers that wantedexperience in the field. During the first year, I also took on a graduate student to work with tree snails, supported by our newGraduate Assistant Program. These students had an opportunity to learn more about the biology of tree snails, plant identification, field metholodology, and limestone forest ecology. These experiences for students are important, as they provided practical training in field research, and exposure to field biology and conservation. Collaborations with various government agencies also provided opportunities for training and personal development. I worked closely with one biological technician from the National Park Service, and trained her to located identify tree snails. These skills will be important for her and her agency, in assessing tree snails at their holdings on Guam and elsewhere. The collaboration allowed us to plan and carry out a relocation of ~300P. radiolatafrom a portion of the Asan Beach Park infested with invasive little fire ants. Consultations with Guam's DAWR and the CNMI's FWS were also mutually beneficial, and enhanced the ability of staff to find, recognize tree snails, and appreciate their conservatoin status. Prior to listing of all the Marianas' extant tree snail species for protection under the Endangered Species Act, USFWS consulted with me frequently about tree snail populations on Guam. Without survey work undertaken for this project, I would not have been able to contribute much to their decisions. How have the results been disseminated to communities of interest?Some of the results of this project and the status of Guam's tree snails have been disseminated to the public. I made a presentation to the UOG Marine Lab's Friday Seminar (POETS) in the Fall, and have given similar lecture to UOG undergraduates enrolled in our environmental biology course. I also presented a tree snail conservation poster at a UOG outreach event targetting local high schools and government agencies on Guam. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
Overview: This project was begun in order to assess the conservation status of the three species of native tree snails on Guam and in the CNMI. Our efforts focused on defining populations, characterizing vegetation use, and predation sources of partulids on Guam. Efforts to conduct work in the CNMI were stalled by extreme weather conditions (i.e., typhoons) and difficulties obtaining permits. In this first year of the project, six additional populations of the Guam tree snail (Partula radiolata) and one additional population of the very rare fragile tree snail (Samoana fragilis) were identified on Guam. This discovery expands the known range of these species, improves our ability to find additional sites, and helps us make conservation recommendations. Except for a few locations, counts of Guam tree snails at most sites were relatively low, and no living native tree snails were found in any of the six sites surveyed on the eastern half of northern Guam. This suggests even the most common and widespread species are at risk. Wherever they did occur, native tree snails could be found on most any plant (both native and exotic). However, they were more likely on broad-leaved plants that either provided canopy or were well shaded by other plants. In locations where typhoon Dolphin damaged forest canopy, fewer snails were found than prior to the storm. We found direct evidence of predation by the Manokwari flatworm (Platydemus manokwari) at several locations, indicating it is a major threat to native tree snails, island wide. In summary, the first year of the study provided good baseline data for the locations of tree snails on Guam, preliminary information on predation and plant use, and established collaborations with various private and public stakeholders in the region. Progress on Objectives 1) ID and Map Partulid Populations a) Conduct surveys on all accessible Mariana islands to locate partulid snails. Several preliminary and a few detailed surveys were conducted on Guam to locate and characterize populations of native tree snails. New populations of Guam tree snail (P. radiolata) were observed at mid and lower Pago River, Asan Spring, Taguag River, Togcha River, Talofofo/Ugum River and Sella Bay river mouth. One small new population of fragile tree snail (S. fragilis) was located at the Sella Bay river mouth, sympatric with P. radiolata. Several survey locations yielded no native tree snails including Fadian, Mt. Santa Rosa, UOG Mangilao, Asiga, Taga'chang, Anigua Coast, and south Oka point. Surveys of tree snails on Rota and Saipan were planned, but could not be carried out due to typhoons and permitting delays in the CNMI. b) Assess population sizes of each partulid snail species found. Monthly counts of S. fragilis were carried out at Hilaan, with population estimates ranging from ~30 to 80 individuals. Two counts of S. fragilis at Sella Bay suggest a population less than 20 individuals. Counts of P. radiolata were made at several locations, but have not yet been evaluated in terms of person hours or area. Most of the new populations found in the first year of this project are relatively small and low density. In contrast, a mark-recapture study conducted at Asan Beach Park in collaboration with the National Park Service, indicates a population of around 1000 individuals on the north side of Asan ridge in the park. c) Accurately map populations using GPS Locations and approximate boundaries of all tree snail populations surveyed in the first year were recorded using GPS unit, and preliminary maps have been generated. 2) Characterize Vegetation a) Identify home plants used by snails in each location during above partulid surveys. Home plants used by snails have been identified in all locations, but not yet been quantified. b) Map vegetation patterns Vegetation pattern data were not recorded for preliminary surveys. c) Quantify usage patterns Vegetation usage was recorded for several surveys, but the data has not yet been analyzed. 3) Characterize & Quantify Predation a) Note occurrence of empty shells in different locations. Empty shells have been collected for monthly surveys at Hilaan, where two native tree snails species are sympatric (P. radiolata and S. fragilis). Empty S. fragilis shells far outnumber those of P. radiolata, despite the fact that the latter species is much more common in that location. Empty shells in other locations have been observed and collected when possible. b) Assess empty shells for evidence of predator damage. Most empty shells lack physical damage associated with rats or terrestrial crabs. In some cases, empty shells were found attached partly attached to substrate by remnants of mucus, and some contained morbid snail tissue. These are consistent with observations of predation by the manokwari flatworm, Platydemus manokwari. c) Record predation events and map presence of known predators. Predation events were fortuitous and have only been observed a few times in the last year, and mostly at Hilaan. All direct observations of predation have involved P. manokwari, and these flatworms have been observed at most of the locations surveyed. d) Undertake detailed predation surveys at specific sites with high mortality levels. Sites for this effort have yet to be determined.
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