http://www.rssboard.org/rss-specification 720 https://escholarship.org/uc/bnhm_ucb_moorea_2012/rss Recent eScholarship items from Student Research Papers, Fall 2012 Fri, 15 May 2026 11:15:51 +0000 https://escholarship.org/uc/item/8jt4w5jj <p>Natural and anthropogenic disturbances are changing coral reef systems at local and global scales. In Mo’orea, French Polynesia, it is unsure whether a Pocilloporid-and Poritid-dominant reef represents either a transitional, recovering community or a new, stable community (Pratchett 2010). Understanding the species-specific associations between coral-symbionts and their coral hosts will provide a more precise look at how symbionts contribute to their relationship. To better understand this mutualism, this study combined field surveys with phylogenetic analyses to examine the species-specific association between Trapezia crabs and their Pocillopora coral hosts and ask more broadly if there is an association between environmental variables and a morphological phylogeny of Trapezia. There was a significant association between certain species of Trapezia and Pocillopora (Likelihood ratio, x²=84.49, df=16, p=&lt;0.0001*), whereT. rufopunctata was found most frequently... https://escholarship.org/uc/item/8jt4w5jj Tue, 18 Dec 2012 00:00:00 +0000 Ly, Vickie https://escholarship.org/uc/item/9q13k5tx Intertidal zonation of organisms is a key factor in ecological community structure and the existence of fundamental and realized niches. The zonation of two species of gastropods,Nerita plicata and Morula granulata were investigated using field observations and lab experimentation. The Nerita plicata were found on the upper limits of the intertidal zone while the Morula granulata were found on the lower limits. The distribution of each species was observed and the possible causes of this zonation were examined. Three main factors, desiccation, flow resistance and shell size were tested for their zonation. In the field, shell measurements of each species were made to see if a vertical shell size gradient existed; the results showed an upshore shell size gradient for each species. In the lab, experiments were run to see if the zonation preference found in the field existed in the lab as well. This experiment confirmed that a zonation between these species does in fact exist. Additional... https://escholarship.org/uc/item/9q13k5tx Mon, 17 Dec 2012 00:00:00 +0000 Wormser, Vanessa https://escholarship.org/uc/item/9d638238 Aquaculture has many effects on the surrounding landscape. In Mo’orea, the only aquaculture operation is a shrimp farm in Opunohu Bay. To test the effect of shrimp farm runoff into the bay, a macroalgae field survey was conducted at different distances from the Opunohu River, where the effluent outlets. Algae cover was used to indicate nutrient concentration. I found that there is no significant relationship between distance from the shrimp farm outlet and algae cover. The red algae Acanthophora spicifera is a cultivated human food source and also a highly invasive species in Hawaii. It is found in Opunohu Bay. To test the effect of shrimp farm runoff on the growth rate of A. spicifera, I grew the algae in a laboratory setting in shrimp farm water and in ocean water. I found there to be no significant difference between the growth rates in the two water mediums. Additionally, I found that algae cover increases as distance from shore increases, and that algae prefers rock substrate... https://escholarship.org/uc/item/9d638238 Mon, 17 Dec 2012 00:00:00 +0000 Horn, Rachel A https://escholarship.org/uc/item/81n5n6bv Abstract.Estuaries are some of the most productive ecosystems in the world; though human development and global warming are threatening them. Zooplankton communities can serve as biological indicators of stresses due to their short lifecycles and sensitivity to environmental shocks, such as salinity changes. Studies have looked at the effects of freshwater shocks in the lab outnumber those that surveyed natural zooplankton distributions change along the freshwater gradient created by outflow from rivers. This study surveys the distribution of various taxa and examines the relationship this has with salinity by sampling zooplankton in Pao Pao River and Opunohu River on the island of Moorea in French Polynesia. In addition, this study tests the ability of copepods native to brackish water in Pao Pao to survive various shocks of increasing or decreasing salinity over time, as well as their response to bright light. Significant differences were found in overall community composition... https://escholarship.org/uc/item/81n5n6bv Mon, 17 Dec 2012 00:00:00 +0000 Piterman, Sergey https://escholarship.org/uc/item/81m5864z <p>Abstract.Much of the recent decline in coral reefs can be attributed to coral disease; however, very little is known about coral immunity. Pink non-nomral pigmented immune response lesions have been seen on massivePoritescoral in Mo’orea. Field surveys were conducted around the island measuring; sedimentation, water flow rate, location in the fringing or back reef and the number ofDendropoma maximumandSpirobranchus giganteusembedded in the coral to test for an association with the immune response. Multivariate linear regression reveals a nearly significant positive association betweenSpirobranchusgiganteusand pink lesions. This study suggestsS. giganteusmay play a role in this immune response or be linked to some other confounding factor. Thus,S.giganteuscould be a potential bio-indicator for coral disease to help aid reef conservation efforts. </p> https://escholarship.org/uc/item/81m5864z Mon, 17 Dec 2012 00:00:00 +0000 Lance, Shannon K https://escholarship.org/uc/item/7vz718v8 THE INFLUENCE OF CURRENT ON THE ADHESIVE POTENTIAL, DENSITY AND ABUNDANCE OF THE MAGNIFICENT SEA ANEMONE (HETERACTIS MAGNIFICA) IN MO’OREA, FRENCH POLYNESIA https://escholarship.org/uc/item/7vz718v8 Mon, 17 Dec 2012 00:00:00 +0000 Lewis, Caroline A, Ms. https://escholarship.org/uc/item/5dd3n01g <p>As secondary producers, zooplankton species are crucial as a vehicle for energy transfer in marine ecosystems worldwide yet few studies have observed the zooplankton community in tropical island estuaries. This study aims to understand the distribution of the zooplankton community in two of the largest estuaries (Opunohu and Cook’s Bays) in the volcanic tropical island of Moorea, French Polynesia. The results show that a few taxonomic groups, especially copepod, dominate the zooplankton composition. Moreover, the zooplankton community and diversity is highly variable at each bay and between bays. In the laboratory, copepod salinity response was examined. Copepods were placed at different salinity treatments for 16 hrs and dead copepods were counted. The salinity experiments show greater mortality of copepods at the extreme ends of salinity concentration, 40ppt and 0 ppt, suggesting that salinity is a major component influencing the abundance in these systems. Monitoring fluctuations... https://escholarship.org/uc/item/5dd3n01g Mon, 17 Dec 2012 00:00:00 +0000 Mendez, Carolina https://escholarship.org/uc/item/5952f5mk This study investigates the biomechanics, behavior, and distribution of urchin species in Mo’orea, French Polynesia to understand how they withstand hydrodynamic forces. Field surveys examined the flow distribution of four species:E. mathaei, Tripneustes gratilla, Diadema savignyiandEchinotrix calamaris. Flow tests were conducted on twoEchinometra mathaeisubspecies to measure spine angle under no flow and heavy flow conditions. Short spine urchin species were found in significantly higher flows than were long spine urchin species. Experimental findings revealed thatE. mathaeitype B temporarily adopts a more streamlined shape in response to increasing flow velocity, whileE. mathaeitype A does not. Understanding the streamlining behavior and other strategies for surviving hydrodynamic conditions is necessary in order to examine these organisms’ role in their environment. https://escholarship.org/uc/item/5952f5mk Mon, 17 Dec 2012 00:00:00 +0000 Weiss, Amelia https://escholarship.org/uc/item/5182x106 <p>Habitat preferences are intrinsically linked to factors that facilitate the survival of a species. The relationship between these factors determines how well a species does in its environment. Often habitat choice is related to the availability of food, presence of predators, and proximity to other viable habitats, amongst other variables. How these variables interact depends on fluctuations in the trophic web of which they are a part.Corythoichthys flavofasciatusis a species of pipefish that occurs in the fringing and back reefs of Mo’orea, French Polynesia. It feeds on zooplankton and occurs primarily on dead coral heads that are covered in algal turf. This study aimed to understand the relationship between zooplankton abundance, habitat quality, and substrate types on the habitat preferences of this pipefish. A field survey of the abundance of zooplankton in different habitats was used to determine if more food was available in habitats that were dominated by dead coral.... https://escholarship.org/uc/item/5182x106 Mon, 17 Dec 2012 00:00:00 +0000 Iyer, Neetha https://escholarship.org/uc/item/41z997bp <p>The importance of disturbance ecology grows as pristine habitat becomes increasingly encroached upon by land use change. This study focuses on the behavior of the burrowing terrestrial crabCardisoma carnifex(Herbst 1794) on the island of Moorea after its semi-permanent burrow was disrupted. In the first manipulation, a set of four disturbance treatments was applied to burrows in sand and dirt substrate to examine recovery time. The second manipulation increased the intensity of the disturbance to see if the crabs’ strategies change. The results showed a significant increase in recovery time with the intensity of disturbance in dirt substrates, but not in sand. There was also a significant combined effect of treatment and substrate type on recovery. The second set of data showed the same set of recovery strategies even as the disturbances were more intense. This shows that these crabs can restore their burrows in relatively low levels of disturbance, but it remains to be seen... https://escholarship.org/uc/item/41z997bp Mon, 17 Dec 2012 00:00:00 +0000 Hurley, Jacqueline https://escholarship.org/uc/item/3977m4tq Anthropogenic increases in atmospheric CO₂ compound the rates of long-term changes in the abiotic conditions of the Earth’s oceans. Because many physiological processes, including calcification rate, depend on these physical factors, there is mounting concern over how changes in temperature (T) and the CaCO₃ saturation of seawater will affect marine organisms.  These effects may be particularly relevant during development— many organisms produce protective calcified structures critical for pelagic dispersal and larval survivability.  I investigated how unmitigated increases in oceanic pCO₂ and temperature consistent with climate change predictions affect the embryonic development rate, hatching success, and veliger morphology of the opisthobranch gastropod,Stylocheilus striatus. Embryos were reared in four seawater treatments: 1) control (pH=8.02, T=27°C), 2) high-temperature (pH=8.02, T=31°C), 3) acidified(pH=7.67, T=27°C), 4) acidified high-temperature... https://escholarship.org/uc/item/3977m4tq Mon, 17 Dec 2012 00:00:00 +0000 Allen, Trevor Riley https://escholarship.org/uc/item/3279865c Communities of non- vascular plants called bryophytes grow on limestone and basalt on Mo'orea, French Polynesia. The abiotic properties associated with living on each substrate is not well known, however. This study looks at the soil pH, buffering capacity, phosphate levels and substrate water holding ability associated with each substrate. In general, limestone has greater water holding capacity than basalt and its soils are more basic, have higher phosphate levels and have a greater pH buffering capacity than soils on basalt. This study also looks at the biological impact of these substrate abiotic differences by using multivariate discriminate analysis to compare bryophyte communities on each substrate. Five species are tightly correlated with a particular substrate. Ectropothecium sandwichense and Floribundaria aerunginosa prefer limestone whereas  Calymperes aongstroemii, Taxithelium vernieri, and Ectropothecium sodale, prefer basalt. Because the distribution of these species... https://escholarship.org/uc/item/3279865c Mon, 17 Dec 2012 00:00:00 +0000 Wu, Jasper https://escholarship.org/uc/item/1td9248w Defense mechanisms have been long recognized as an important factor in establishing the development of many organism life histories. As a result, many processes associated with ensuring survivability have been very well established in organisms that utilize defense mechanisms. How these defense mechanisms have shaped the evisceration and regenerative processes of sea cucumber Holothuria leucospilota still remain largely unstudied. In this study it is revealed that Holothuria leucospilota remain very consistent in their modes of evisceration, ejecting the same organs in every evisceration event. The consistency is compounded by the finding that approximately 28% of their body mass is eviscerated regardless of organism size. In terms of organ regeneration, the thickening of the mesentery tissues is apparent at Day 4 and regeneration of the digestive tract at Day 16. Sediment feeding also resumes at Day 16 along with the regeneration of the digestive tract. No regeneration of the... https://escholarship.org/uc/item/1td9248w Mon, 17 Dec 2012 00:00:00 +0000 Hsieh, Vicki https://escholarship.org/uc/item/6tq3k5dh Epifoliar fungi are understudied, despite high prevalence across plant tissue. In this study, conducted on the island of Mo’orea, French Polynesia, an epifoliar fungus found on a high diversity of native leaves was identified and characterized. The rate of development was tracked and the characteristics of colonization were determined on mangrove ferns. Environmental conditions did not affect distribution, but did affect the growth rate of the fungal fruiting body. Host distribution was also surveyed and the fungi primarily occurred on naturalized plants. The potential use of this fungus as a bioindicator of plant and habitat health will be discussed. https://escholarship.org/uc/item/6tq3k5dh Sun, 16 Dec 2012 00:00:00 +0000 Dasari, Mauna https://escholarship.org/uc/item/5n2925sj Social structures and population ecology can greatly influence individual behaviors in animal societies. The Common Myna (Acridotheres trisis) is a social, aggressive bird that is known as one of the world’s worst invaders. On the island of Mo’orea, French Polynesia,A. tristisis most often found in pairs and groups. It was anticipated that a pair ofA. tristiswould act as a team to increase foraging and defense efficiency. This study examined aggressive behaviors using behavioral observations ofA. tristisin pairs and groups on two different sites on the island. Food was added to the sites to determine how food availability may affect behavior. The results show that being in a group setting significantly increases aggression. A look at non-aggressive behaviors provided information on the most common behaviors seen inA. tristisboth in groups and pairs. Furthermore, the addition of food significantly increases aggression. The aggressive behaviors seen were increased with group type... https://escholarship.org/uc/item/5n2925sj Sun, 16 Dec 2012 00:00:00 +0000 Mohan, Regina https://escholarship.org/uc/item/51f3q99p <p>Regeneration is common amongst all classes of echinoderms and is easily studied in the laboratory with abundant and tractable ophiuroid specimens. However, ophiuroid regeneration rates, both between species and within the same species, can exhibit uncommonly high variation even under identical laboratory conditions. Eighty-four Ophiocoma scolopendrina (Lamarck 1816), a brittle star which extends its arms out into the water column to suspension feed, were collected from the upper-intertidal zone of rocky beaches on the island of Moorea, French Polynesia for laboratory regeneration experiments. To determine the effects of position of autotomy and feeding level on regenerated length and differentiation of new biomass, two treatments were performed: an amputation treatment either 5 mm from the central disk or 30 mm from the distal tip; and a feeding treatment of high-food or low-food. Additionally, a field survey was conducted to assess predation pressure and autotomy of O. scolopendrina... https://escholarship.org/uc/item/51f3q99p Sun, 16 Dec 2012 00:00:00 +0000 West, Elaine Allison https://escholarship.org/uc/item/26t6g09d <p>A controlled observation study was used to determine differences in athropod communities on fruits introduced to the island of Mo’orea, French Polynesia, approximately 300 and 1000 years ago respectively: papaya (Carica papaya) and Tahitian chestnut (Inocarpus fagifer), in two regions: an agricultural school and a tropical moist broadleaf forest. Distinct differences in communities existed by fruit and region, and there was interaction between the influence of region and fruit type. Papaya communities showed the most differences by region. Papaya communities had a greater mean number of individuals and taxa than Tahitian chestnut communities. Region did not have a significant effect on the mean number of individuals and taxa, but for both individuals and taxa the forested region showed more variation in the communities found on each fruit than in the agricultural region, perhaps due to greater niche differentiation (competition among species), on the less frequently disturbed... https://escholarship.org/uc/item/26t6g09d Sun, 16 Dec 2012 00:00:00 +0000 Starrs, Genoa Ione https://escholarship.org/uc/item/5524p5x6 Coloration in relation to ecology in the Asian spiny-backed spider, Thelacantha brevispina (Araneae, Araneidae) on Moorea, French Polynesia https://escholarship.org/uc/item/5524p5x6 Wed, 12 Dec 2012 00:00:00 +0000 Truong, Hua https://escholarship.org/uc/item/0b72h9z2 Crabs of the species <em>Dardanus pedunculatus</em> form a symbiotic relationship with <em>Calliactis tricolor</em> anemones on Moorea, French Polynesia. Crabs actively collect anemones for protection against octopus predation, while simultaneously giving the anemones a better habitat, defense against predators, and food as a result of the crab’s messy eating. In a laboratory setting, crabs will compete for anemones with larger crabs winning competitions. This paper examined crabs’ field collection patterns, and found that larger crabs collect more anemones, cover a greater percentage of their dorsal side with anemones, and carry a larger volume of anemones than smaller individuals. An experiment was designed to determine collection preference when unimpeded by field restrictions, and found that larger crabs show similar collection patterns as in the field, while smaller crabs cover a greater percentage of their dorsal side with anemones than in the field. This implies that abundance... https://escholarship.org/uc/item/0b72h9z2 Wed, 12 Dec 2012 00:00:00 +0000 Atkinson, Lesje https://escholarship.org/uc/item/09v1g69f Plant-insect symbiosis and succession are important components of tropical ecosystems for understanding natural history and biodiversity. There are not many studies of gall succession and gall life cycles in tropical environments, even though it is an important component of tropical ecology. A number of gall specimens onSyzygium malaccense were followed over time, sampled for insect communities, and tested for areas of fungal coverage to determine if they underwent successional development and caused leaf decay outside the gall boundaries. Different gall stages were classified over this time period and were found to contain different communities. Desiccation and decay were found to cause gall color change, and the decay was limited to the gall boundaries avoiding theS. malaccense leaf.Syzygium malaccense galls were thus found to model succession, and also present a unique symbiotic system amongst a diverse set of tropical organisms. https://escholarship.org/uc/item/09v1g69f Wed, 12 Dec 2012 00:00:00 +0000 Au, Stephanie