Ka Pili Kai University of Hawaiÿi Sea Grant College Program Vol. 29, No. 3 Fall 2007
Graduate Student Research An Age of Discovery University of Hawai‘i Sea Grant College Program
Ka Pili Kai (ISSN 1550-641X) is published Ka Pili Kai Vol 29, No. 3 quarterly by the University of Hawaiÿi Sea Contents Grant College Program (UH Sea Grant), School of Ocean and Earth Science and Technology (SOEST). UH Sea Grant is a unique partnership of university, government and industry, 3 Megaptera-Blog: A Morning in the Life of A focusing on marine research, education and advisory/extension services. Humpback Whale University of Hawai‘i mproving rediction for the nundation of eef Sea Grant College Program 6 I P I R - 2525 Correa Road, HIG 208 Fringed Coastlines Honolulu, HI 96822 Director: 8 He‘eia Fishpond: The Nutrient Story E. Gordon Grau, Ph.D.
10 Could Microalgae Be the Key to Adaptation in Communications Leader: Cindy Knapman Coral Reefs? Multimedia Specialist: Heather Dudock 12 Long-Term Movements of Reef Fish within the Periodicals postage paid at Honolulu, HI Kealakekua Bay No-Take Marine Protected Area Postmaster: Send address changes to: 14 The Effective Management of Healthy Ka Pili Kai, 2525 Correa Road, HIG 208 Honolulu, HI 96822 Parrotfish Populations (808) 956-7410; fax: (808) 956-3014 uhsgcomm@hawaii.edu www.soest.hawaii.edu/seagrant
The University of Hawaiÿi was designated a Sea Grant College in 1972, following the National In this issue of Ka Pili Kai... Sea Grant College and Program Act of 1966. Ka Pili Kai is funded by a grant from In the last issue of Ka Pili Kai our readers traveled to the shores of the National Oceanic and Atmospheric Administration, project M/C-1, sponsored by the Marshall Islands, to the vibrant coral reefs and Marine Protected the University of Hawaiÿi Sea Grant College Areas of Hawai‘i, and into the laboratory to study microscopic Program/SOEST, under Institutional Grant No. NA05OAR4171048 from the NOAA Office biofilms, all through the eyes of graduate students supported by the of Sea Grant, Department of Commerce. University of Hawai‘i Sea Grant College Program’s Graduate Trainee The views expressed herein are those of the Program. Thanks in large part to the overwhelming response we authors only. received from this issue, coupled with the fact that we were only able UNIHI-SEAGRANT-NP-08-05 to highlight a small number of these talented individuals, we opted Ka Pili Kai Editor: Cindy Knapman to once again dedicate an entire issue to exploring graduate student Layout and Design: Heather Dudock research. On the Cover: Ocean navigators in the Marshall Islands use traditional In this issue, journey with us to the open ocean in search of humpback techniques and indigenous seamarks whales, to the shoreline in an effort to predict coastal inundation, and to sail without the use of instruments. underwater to study reef fish and coral reefs throughout Hawai‘i. We This photo was taken by Joseph are proud to once again provide a glimpse of the fascinating work Genz, UH Sea Grant-supported graduate student, during his research being conducted by these students who are poised to become leaders and field study regarding traditional in their field. ocean navigation in the Marshall Islands. Cindy Knapman, Communications Leader
2 Ka Pili Kai Ed Lyman
Megaptera-blog: A morning in the life of a humpback whale By Alison Stimpert, UH Sea Grant-supported graduate student
About me: I am an adult male humpback whale, and I’ve come to spend the winter in the sunny Hawaiian islands. I’ve heard that there are lots of available women here! I like breaching, singing, and long swims past the beach.
Because of the difficulty in studying large marine mammals in the field, one of the steps to understanding the behavior of a species is to look first at individuals. Our lab is studying the acoustic behavior of humpback whales here in Hawai‘i in order to better understand how the whales may use sound as social communication, and ultimately how this communication might be influenced by ocean noise. We use non-invasive, suction-cup tags that record sound and body movements of the tagged animal. In this way we can “observe” the whale’s swimming and acoustic behavior underwater as well as at the surface. Here we take a look at a typical research day, as we follow the activities of one of our tagged whales from this past winter season during a tag attachment of several hours.
Friday, March 2, 2007: 9:35am Group type: 8 adults/competitive
Start the morning off right When we first came across our tagged whale, he was part of a competitive group of whales. As with most competitive groups, there was a presumed female in the center of the group, and the rest of the surrounding whales are almost always male (which is why we can assume our tagged whale was
3 Ka Pili Kai male as well). other adults, creating a three-adult group that was These males pretty active! There was not really a consistent fight amongst pattern to their swimming or dive times, and it themselves to wasn’t even clear if there was a female in this group. get as close to The whales kept switching places with each other, the female as and sometimes would throw parts of their bodies possible. The out of the water in surface active displays. When we closest male got the data back, we found that there were lots of to the female sounds being made too – almost twice as frequently is called the as when the tagged whale was part of the larger primary escort, competitive group. But it still was not clear what and he was was going on. making lots of aggressive visual Friday, March 2, 2007: 10:56am Ed Lyman displays like Group type: Mom, calf, and three escorts/ Stimpert sets up tracking equipment. blowing bubbles competitive and lunging out of the water. There were quite a few sounds being produced as well. The sounds Found another female we have recorded in competitive groups so far are Shortly thereafter, a mom/calf pair appeared in the short in duration, and not as loud or as melodic as vicinity. Though the average female humpback the famous humpback whale song. These sounds fit only has a calf every 2 – 3 years, sometimes they that pattern. The whale we ended up tagging was will calve in successive years. For a male looking a secondary escort who remained on the outskirts for mating opportunities, hanging with a lactating of the group (this made it easier for us to approach female still seems to be a better bet than being him). alone. Our tagged whale joined the mom Friday, March 2, 2007: 9:50am and calf along with the Group type: single/travel pair from the previous group. Hardly any Lookin’ for love… sounds were happening After less than half an hour, our tagged whale left in this group, but there the competitive group and began traveling alone in a was a definite fight westerly direction. With no way of predicting where for proximity to the he would go, we just followed behind at a distance female! Luckily, our and continued recording data. tagged whale seemed to hold his own, and Friday, March 2, 2007: 10:08am eventually the other Group type: 3 adults two whales headed off Michael Richlen to join up with a nearby Aran Mooney (left) takes photos and …in all the wrong places pair. Stimpert (right) records data. In short order, our tagged whale surfaced with two
4 Ka Pili Kai to stay with a mom/calf pair, when that female may not be receptive, is still not fully understood. We are also still learning about what the sounds produced in these contexts mean. That’s where our lab comes in. By looking at the behavioral contexts in which we record certain sound types, and through acoustic comparisons with sounds on the feeding grounds and the migration route, we’re hoping to draw conclusions about how the whales might be using sound to communicate Stimpert/OSI during these breeding activities. This will allow Friday, March 2, 2007: 11:10am us to formulate Group type: Mom, calf, and me educated opinions on how increased Hangin’ with mom and calf anthropogenic Finally, a chance to relax. Once the group noise levels dwindled to just mom, calf, and the tagged whale, will impact the all three stopped traveling. That meant mom and whales in various the tagged whale sat stationary at about 60 feet behavioral states. in depth. The calf has to breathe more frequently than they do, so he rose to the surface every four minutes or so, swam in a circle around where mom was resting, and then dove back down to her. This lasted for the rest of the tag attachment, until it Aran Mooney detached and we were happily able to recover all Stimpert programs a tag. the data!
As we can see from the behavioral patterns of this whale, associations between whales on the breeding grounds tend to be somewhat transient. We believe that most interactions are driven by the male goal of finding female mates, but humpback mating has actually never been documented. Shifting Aran Mooney amongst different types of groups may indicate a search for appropriate females. Why a male may choose
Stimpert during a successful tagging attempt.
5 Ka Pili Kai Improving prediction for the inundation of reef-fringed coastlines By Christine Péquignet, UH Sea Grant-supported graduate student
have often wondered, what happens to the amount of energy that is Ibrought to the shore by ocean waves? Now, as part of my graduate work, I have the chance to answer this question and what a better place to do so than in Hawai‘i.
This question is actually also being asked by coastal zone managers, who would like to be able to predict coastal inundation. Along wide continental shelves, a wind-driven storm surge tends to be the leading cause for coastal inundation. Along tropical island coasts, high waves, often generated by remote storms, pose a more immediate threat. Around the Hawaiian islands, large waves occur throughout the year generated by north and south Pacific extra-tropical storms, east Pacific tropical storms and hurricanes, and extreme local Kona and trade wind conditions. A recent survey of damaging wave events around the island of O‘ahu
Susanne Pridoehl illustrates that all sides of the islands are at risk. High surf conditions lead to overwash of beaches and coastal barriers causing road closures, property damage, and coastal erosion. Given the prevalence of these events and the probability that their frequency and impact will increase as global sea levels continue to rise, it is imperative that coastal zone managers who are responsible for environmental conservation, coastal hazard mitigation, and ocean safety acquire detailed information about extreme wave impacts including an assessment of risk for Hawai‘i beaches and shorelines.
The goal of this project is to assess and predict the amount of wave energy that reaches the shoreline of reef dominated coasts for a given set of wave and water level conditions. This project is built upon our recent participation in the Army Corps of Engineers-sponsored Pacific Island Land Ocean Typhoon (PILOT) experiment, which was focused on the reef-fringed beach in Ipan, Guam. As part of this University of Hawai‘i Sea Grant College Program project, we are extending the work done in Guam to two other sites on O‘ahu’s North Shore (Mokulei‘a and Waimea Bay) to address the variety of reef topographies. We are using a system of video cameras to monitor the waterline evolution at time scales of seconds to weeks. Susanne Pridoehl
6 Ka Ka Pili Pili Kai Kai The estimation of coastal inundation begins with high quality measurements of deep water wave conditions. The University of Hawai‘i Department of Oceanography has operated a series of Datawell directional wave buoys since 1999 around O‘ahu Normal sea level
(http://soest.hawaii.edu/buoy). The buoy that is Run-up deployed approximately 4.3 nautical miles west of Sunset Point acquires data from a depth of 200 meters and is used to obtain offshore wave conditions for the of the water line due to the presence of waves and sites on the North Shore. is measured from digital video images. In Guam, a Coastal Data Information Program operates So far, we have measured the efficiency of reef a wave buoy deployed to the south of Ipan Beach environments to dissipate wave energy through that is used to determine offshore conditions. Near wave breaking and friction associated with the the shore, a series of wave gauges and current meters rough topography of coral reefs. Although the same processes are involved in the dissipation of waves on sandy beaches, the intensity of these processes and their spatial and temporal signatures are very different on reef dominated coastlines. Comparison between the different sites shows that the topography of the reef is critical in trying to predict the shoreline energy and can not be simply parameterized in terms of a slope as it is done on sandy beaches. In locations where or during conditions when breaking and friction are not enough to dissipate all the wave energy, the shoreline often develops into a steep topography that allows the wave energy to be reflected back to sea. Strong reflection is associated with large
Susanne Pridoehl run-up, or large oscillation of the water line. This winter season on the North Shore of O‘ahu we are Péquignet determines the porosity of the Ipan reef, Guam. hoping to gather more data from big wave events to complement our dataset and help us to better predict extreme run-up events. are deployed across the reef. The data from these instruments is used to estimate where and how much of the wave energy is dissipated and to estimate the amount of wave energy reflected at the coast. Wave energy at the shoreline is described in terms of wave run-up. Run-up is defined as the time-varying location
7 Ka Pili Kai He‘eia Fishpond: The Nutrient Story By Rebecca Briggs and Chip Young, UH Sea Grant-supported graduate students
e‘eia Fishpond is a fully enclosed, 88 acre, oxygen conditions and how these reactions affect P loko kuapä (seashore pond), located within and Fe cycling within He‘eia Fishpond. H Käne‘ohe Bay on the island of O‘ahu. Loko kuapä are made by enclosing a portion of the shallow The Sediments coastal reef waters within a stone wall. The positioning Marine sediments are the locus of intense nutrient of He‘eia Fishpond is not by chance, as its location cycling, and can function as both a source of recycled allows fishpond managers to balance the water quality nutrients back into the water column for biological of the pond by taking advantage of both fresh and salt uptake, or a sink, capturing nutrients from the water inputs to promote conditions that benefit their water column and rendering them unavailable to desired harvest. For centuries, fishponds throughout organisms. The elemental reactions occurring within the Hawaiian islands have been used for aquaculture, the sediment column can have profound effects on cultivating fish and limu (edible seaweed) to feed the the concentration of nutrients in the overlying water, surrounding community. The age of He‘eia Fishpond which in turn will directly impact water column is unknown, however maps of He‘eia Fishpond date primary production. back to the early 1800’s. He‘eia Fishpond currently is under the jurisdiction of Kamehameha Schools Bishop To arrive at a quantitative understanding of coupled Estate and managed by Paepae o He‘eia, a private Fe-P cycling in nearshore environments, it is non-profit organization. necessary to identify the fundamental processes controlling their concentrations both in the water Our research interests are in understanding how and at the sediment-water interface. In many sediment and nutrient loading affect the water quality environments, seasonal changes in sediment oxygen of He‘eia Fishpond. Paepae o He‘eia is particularly conditions can alter the direction and magnitude of P interested in understanding how sediments impact and Fe fluxes across the sediment-seawater interface nutrient cycling, as they have observed that pond and, thus, influence water column nutrient inventories health has declined in concert with increased sediment and ratios. An important objective of this project loading in the pond. Phosphorus (P) and iron (Fe) is to determine whether redox control of benthic P are essential nutrients required by photosynthetic and Fe fluxes primary producers (phytoplankton, macroalgae). may also occur As such, the impact of sediment on retention and/or on a diurnal release of P and Fe could impact ecosystem health timescale. and functioning. Prior to entering the oceans both P Specifically, we and Fe may undergo extensive, often coupled, cycling will investigate in coastal marine environments. Our research focuses how diel shifts in on the coupled Fe-P cycling in He‘eia Fishpond, redox conditions with a primary goal of quantitatively determining the that accompany influence these elements have on biological activity diel changes in and ecosystem functioning within the pond. photosynthesis (oxygen- This project is led by professors Kathleen Ruttenberg, producing) Brian Glazer, and Margaret McManus of the and respiration University of Hawai‘i at Manoa in collaboration with (oxygen- Paepae o He‘eia. Our study has significant historical consuming) and local resonance with the Hawaiian community, reactions within as it provides the first look at sediment influences on the sediments nutrient cycles within a historic Hawaiian fishpond affect P and Fe and will provide insight into the ways in which cycling in He‘eia anthropogenically enhanced sedimentation may Fishpond. affect native fish and limu growth. Our work focuses particularly on (1) the dynamics and biogeochemistry The fieldwork of terrestrial nutrient inputs to the fishpond, and their for this study NOAA role in overall pond nutrient budgets; and (2) sediment involves the Satellite view of He‘eia Fishpond indicating reactions driven by diel (day-night) shifts in sediment collection of the locations of the seven mäkähä. x = instrument locations 8 Ka Pili Kai * = water sample sites sediment cores and bottom water during a series to the coastal ocean. This implies that diagenetic of diel experiments at selected sites in He‘eia mobilization after sedimentation on the seafloor, Fishpond. Quantification of dissolved and solid rather than simple desorption upon river-ocean phase nutrients are made through traditional pore mixing, could prove to be the primary pathway for water and solid-phase methods, benthic flux P release from RSPM. Our work seeks to identify measurements, as well as newer electrochemical and quantify the specific reservoirs of bioavailable techniques that are uniquely adapted to making P released from RSPM as river water mixes fine-scale biogeochemical measurements at and near with coastal seawater and particles are subjected the sediment-water interface. These analyses permit to increasing ionic strength. This data can be flux calculations to be made in order to determine the juxtaposed to the sediment benthic flux data in order magnitude and direction of nutrient fluxes across the to compare, quantitatively, the pathways for nutrient sediment-water interface, and to place these fluxes input to the pond. within the context of a pond-wide nutrient budget. Finally, with the nutrient budget constructed, The Water Column including storm and bottom sediment inputs, we will The three principal goals of the water column portion link observed changes in phytoplankton community of the study are to (1) create a monthly nutrient composition to temporal changes in water column budget for the pond, (2) quantify the impact of storm bioavailable nutrient inventories and nutrient ratios. runoff on nutrient budgets, and (3) observe how Because He‘eia Fishpond is a controlled, nearshore temporal variability in pond nutrient inventories and environment, it affords a rare opportunity to nutrient ratios impact phytoplankton community quantitatively measure and model nutrient cycling composition. In order to create a nutrient budget processes and linked ecosystem dynamics. for the pond, nutrient sources and sinks must be quantified. Rivers are a nutrient source, and adjacent In summary, there are three principal goals of this Käne‘ohe Bay can serve as either a nutrient source work. (1) Identify and quantify the mechanisms or sink. To estimate the magnitude of these nutrient controlling seabed retention and release of essential transport pathways, the primary physical processes (limiting) nutrients P and Fe. In particular, we that drive flow and transport to and from the pond wish to examine the novel idea that benthic (wind, waves, tides and freshwater discharge via photosynthesis plays a role in coupled Fe-P cycling; streams and/or groundwater infiltration) must be (2) Quantify nutrient budgets for He‘eia Fishpond, quantified. There are seven mäkähä (gates) which are including the effect of storms on riverine P, Fe, the avenues through which freshwater and saltwater Nitrogen (N), Silicone (Si) input to the pond, enter and leave the fishpond. We have instrumented including evaluation of the relative importance of the seven mäkähä to quantify water movement external (riverine) vs. internal (benthic flux) nutrient into and out of the pond. Nutrient concentrations, loading; (3) Evaluate the imprint of nutrient delivery measured monthly at 30 sample sites throughout the and subsequent in-pond biogeochemical reactions fishpond, will be linked to the flow measurements on bioavailable nutrient ratios in the fishpond in order to quantify nutrient sources and sinks to the linking the occurrence of shifting nutrient ratios pond. to changes in pond limiting nutrient status and phytoplankton community composition. Ultimately, Rivers are the primary source of the bio-limiting our study will result in the construction of seasonal elements P and Fe to the oceans. Due to their nutrient budgets for He‘eia Fishpond, including a extreme insolubility, most P and Fe in rivers are quantitative assessment of P and Fe input via stream associated with riverine suspended particulate matter influx, storm runoff, and benthic sediment reactions; (RSPM). The impact of land discharge on nutrient identification of the mechanisms that result in delivery to the coastal ocean tends to be amplified sediment P and Fe retention or release, quantified in coastal marine systems adjacent to urbanized or on a diel and seasonal basis; and determine the agriculturally developed regions. This is also true impact of storm runoff on pond nutrient inventories, for He‘eia Fishpond, as this area often experiences nutritional status, and composition of phytoplankton. elevated levels of nutrients, pollutants, and turbidity. These outcomes will be significant both in terms Evidence suggests that substantial P release from of fundamental questions about the effect of RSPM occurs in the river-ocean transition zone. P benthic photosynthetic activity on coupled Fe-P speciation studies suggest that the Fe bound-P and cycling, nutrient transport from land to the organic-P reservoirs are primarily responsible for coastal ocean, and the effects of enhanced this P release. Previous research by Dr. Ruttenberg erosion on the biogeochemistry of coastal has suggested that the release of P from RSPM as a environments, as well as for the practical consequence of changes in ionic strength alone may matter of improving the health of He‘eia account for only a small part of bioavailable P release Fishpond. 9 Ka Pili Kai Could microalgae be the key to adaptation in coral reefs?
By Lisa Adams, UH Sea Grant-supported graduate student
oral reefs are the most diverse and productive a heat tolerant strain of zooxanthellae may be Cof all marine ecosystems and are commonly able to survive in warmer waters. Ultimately, the referred to as the rainforests of the sea. This symbiont plays a crucial role in determining the fate productivity is in part due to the symbiosis of the host throughout its lifetime under varying between coral reef invertebrates and microalgae, environmental conditions. known as zooxanthellae. A wide variety of marine invertebrates, including giant clams, anemones, Different host species acquire zooxanthellae through jellyfishes, and corals have these symbiotic partners different mechanisms. Some host species can inherit living in their tissues. their zooxanthellae from their mothers via eggs. Others must Both symbiont partners benefit from obtain their algal partner from this relationship. Zooxanthellae not the environment surrounding only receive shelter, but also a variety them. Getting zooxanthellae from of nutrients that are byproducts the environment may give each from the hosts metabolism. For generation the opportunity to example, waste is recycled and highly form a symbiosis with the most beneficial to the algae. In return, ecologically fit strain for the hosts have a direct oxygen supply, local environmental conditions. which is produced by the algae during If coral larvae find themselves photosynthesis. Most importantly, on a reef with particularly warm however, zooxanthellae give 95% sea temperatures, they may of the sugar they produce during take up a symbiont that is best photosynthesis to their host, which suited for these conditions. This provides most of the host’s nutritional needs. process may be key in the adaptation of coral reefs to climate change. Zooxanthellae are quite diverse and consist of eight large taxonomic groups, referred to as clades. The well-known and ever-increasing phenomenon of Within each clade are different strains. Although bleaching is when zooxanthellae die or are expelled we know quite a bit about the genetic differences from the host due to stress. The most common of between different types of zooxanthellae, we know stressors is increased sea temperatures. However, very little about their physiological or ecological other stressors including increases in sedimentation, differences. Thus far, researchers do know that great nutrients, and UV radiation, can also induce variation exists in the environmental tolerances bleaching. If the stress does not kill the host animal, between different types of zooxanthellae. In it may be able to recover by taking up a new, free- symbiotic relationships, hosts are, in part, governed living strain from the environment to re-establish by the physiological parameters of their symbiont. a symbiotic partner. After a bleaching event this Consequently, a coral colony that has taken up process may be key for the recovery and future
10 Ka Pili Kai resilience of coral allow free-living zooxanthellae cells to migrate reefs. between the water column and reef sediments. This would also help keep the cells from getting buried If larvae by constant sedimentation on the seafloor. Finally, and adults of zooxanthellae cells kept in culture have been shown some species to have negative responses to turbulence; thus, must acquire in the natural environment zooxanthellae may be zooxanthellae from retreating to the substrate for protection. the environment, then there must be pools of diverse In my studies, I use molecular genetics to locate and viable free-living zooxanthellae somewhere in zooxanthella DNA in the water column and the environment that hosts are utilizing. One of the sediment samples on coral reefs. Molecular genetics persisting mysteries of zooxanthellae is the basic is a powerful tool that allows me to detect the ecology of these microalgae outside of hosts. presence and diversity of zooxanthellae. Identifying the diversity of free-living zooxanthellae that are The research I am conducting at the University present for hosts to utilize is an important step in of Hawai‘i at Hilo with Dr. Misaki Takabayashi trying to understand how symbiotic invertebrates, is aimed at finding the populations of free-living like corals, might adapt to climate change in the zooxanthellae, comparing their diversity in these future. populations to those living in symbioses, and determining if they are viable and accessible to Although molecular genetics will reveal the symbiotic invertebrates. presence and diversity of free-living zooxanthellae, further research is needed to ascertain which Current research has identified free-living of these populations are used by symbiotic zooxanthellae in the water column and marine invertebrates. To determine this, I will expose sediments, though evidence suggests the primary non-symbiotic coral larvae to natural, free-living habitat to be reef sediments. These algal cells zooxanthellae populations in controlled aquaria to are very round and smooth in shape, with a low look for the uptake of zooxanthellae which may tell surface area to volume ratio, and weak mobility. us which population hosts are utilizing. These traits would cause a cell to sink quickly. Other phytoplankton have very elaborate outer This research is likely to serve as a platform shells with many spines, or some cells have a for many related research projects concerning strong flagella for swimming to help slow the adaptation of coral reefs to global climate change. rate of sinking. Furthermore, outside of the host, In addition, the knowledge gained from this zooxanthellae would be very nutrient deprived and research will greatly enhance our understandings of may be attracted to the profuse subsurface nutrients the effects of disturbances and the sustainability of in marine sediments. Nutrients like nitrogen may coral reef ecosystems. play an important role in free-living zooxanthellae ecology. Some microalgae have been found to have minimal buoyancy control by incorporating forms of nitrogen into a storage compartment in the cell, known as the vacuole. Buoyancy control might
11 Ka Pili Kai Long-term movements of reef fish within the Kealakekua Bay no-take Marine Protected Area By Yannis Papastamatiou, UH Sea Grant-supported graduate student
Kim Anthony
he human population of Hawai‘i has under scientific permits). The simple Talways had an important relationship theory behind MPAs is that adult stocks with the ocean. Historically, the of fish will be protected, and through the harvesting of reef fish and invertebrates production of larvae and fish recruits, for food has been an important component they will replenish fished stocks outside of the Hawaiian diet, but traditionally of the MPA. In addition, it is hoped that these resources were only harvested for as the population of adult fish inside the food and not for economic purposes. The MPA increases in size, some individuals situation has changed greatly over the last will relocate outside of the MPA and 100 years with the increase directly improve fishing in the human population, yields (known as spill- commercial and sport fishing, over). However, major tourism, and the aquarium questions still remain trade. As a result of these including how do MPAs fishing pressures, it is well work and how can we known that several fish and design them to be as invertebrate stocks have been efficient as possible? Of in steady decline throughout particular importance the main Hawaiian islands. is an understanding of To counteract these declines, the movement patterns fishery managers have Kim Anthony of the fish that the MPA implemented a number Captain Cook monument, is supposed to protect. of management plans, Kealakekua Bay. If the fish use an area including size and slot limits, (the home range) larger fishing quotas, and seasonal closure of than the area of the MPA, then they will various fisheries. In recent years, a tool only partially be protected from fishing of increasing importance to fisheries pressure. Ideally, we need to design MPAs managers are no-take Marine Protected that are larger than the Areas (MPAs). MPAs are areas where home range used by the no harvesting of marine organisms is fish species. Furthermore, allowed (with the exception of those we need to understand
12 Ka Pili Kai which habitats fish select for and how the MPA is protecting reef fish within the habitat effects their movements. This is of bay, especially because Kealakekua is particular importance to Hawai‘i, as most only 1.3 km². Is the MPA large enough? Hawaiian MPAs are small (<1 km²). Does the MPA contain the right habitat for fish to establish home ranges and remain We are utilizing technology known as within the bay? We have strategically acoustic telemetry to answer these placed underwater listening stations questions. Telemetry transmitters are throughout Kealakekua Bay, and along the small devices that emit a high frequency coastline outside of the MPA. We have been acoustic signal. We catch reef fish and tagging several species of reef fish with surgically implant the transmitters into long-life transmitters (minimum battery their body cavities. Throughout the MPA life one year) to look at their long-term movement patterns. We have been tagging fish from a number of guilds including herbivores, carnivores and planktivores. Data collected to date shows that most fish do spend the majority of their time within Kealakekua Bay, but some individuals shift their home range outside of the MPA after several months. Furthermore, natural habitat breaks like sand-channels may be sufficient to prevent fish from leaving the MPA. These important tools will Kim Anthony enable us to design more efficient MPAs Papastamatiou implants a transmitter within a with the hope that reef fish numbers can parrotfish from Kealakekua Bay. start returning to healthy levels. we strategically place underwater listening stations. Anytime a transmitter-equipped fish swims within range of a listening station (range is generally 300-500 m), its presence is recorded, and by regularly downloading the receivers we can get an idea of the long-term movement patterns of the fish.
Kealakekua Bay, located off the coast of Kona, is historically and culturally of great importance to the people of Hawai‘i. Due to its aesthetic and cultural qualities, the bay was designated an MPA in 1969. However, we still lack an understanding of whether
Kim Anthony
13 Ka Pili Kai The Effective Management of Healthy Parrotfish Populations By Katie Howard, UH Sea Grant-supported graduate student
arrotfish, or uhu (family Scaridae), are some and laboratory research conducted on parrotfish of the most popular reef fish in Hawai‘i, both through HCFRU. P for food and aesthetic value. As herbivores, parrotfish are important ecologically in helping to Results of this study crop macroalgae and maintain healthy corals, as will be used with well as in their role as bioeroders. While feeding, current fish surveys parrotfish scrape off bits of hard rock or dead coral conducted throughout along with their algae. The hard substrate is ground Hawai‘i by local up in the fish’s pharyngeal mill producing a fine researchers to develop sand. a more comprehensive view of both the current Despite how important these fish are, we currently status of Hawaiian know little about uhu in Hawai‘i, which makes it parrotfish populations difficult for fisheries managers to employ important as well as the best decisions regarding parrotfish populations. Basic strategies for effective life history, reproduction, movement and population management. Our assessment data is among the critical information project investigates needed to better understand what management some of the most Tim Clark strategies would work and how they should be important information implemented to attain effective management and for these first steps in Howard and a recently tagged parrotfish. healthy parrotfish populations. effective management: reproduction, movement and behavior, age and Beginning in 2005, the Hawai‘i Cooperative growth, and a basic stock assessment for O‘ahu. Fishery Research Unit (HCFRU), led by Dr. James Our studies have particularly focused on Scarus D. Parrish, began research to attain some of this rubroviolaceus, the redlip parrotfish, since it is basic information that is so crucial to effective the most heavily targeted species in the parrotfish management. fishery. With the help of numerous field Reproduction and lab assistants For almost all modern fishery management (Brett Schumacher, techniques, an understanding of the reproductive Danielle biology of the fishes being managed is critical. Jayewardene, Ling Currently, the parrotfish fishery is managed almost Ong, Nick Whitney, exclusively with minimum size limits. Minimum Jim Hawhee, Tim size limits are typically placed at a size when Clark, and Kelly about 50% of the population has reached maturity, Boyle), I am allowing fish to reproduce before being exposed leading the field to fishing pressure. Unfortunately, we currently do not have robust estimates for when maturity occurs Howard’s colleague, for parrotfish in Hawai‘i. In addition to the size Tim Clark, range tests or age when fish become reproductively mature, acoustic receivers for tracking research. we are also investigating the duration and timing Kelly Boyle of spawning, the number of eggs produced by a 14 Ka Pili Kai female in a given batch and how this might relate to the size of the female. sanded down to a thin section, rings on these otoliths can be read As an interesting complication in understanding like the rings of a tree. We are also parrotfish reproduction, parrotfish are sequential, keeping some fish in captivity at protogynous hermaphrodites, meaning that most the Hawai‘i Institute of Marine individuals mature as females and are later able to Biology located on Coconut change sex and become males. The dynamics of Island in order to verify that the when and why a particular individual makes this ring we see on the otolith is in fact change is poorly understood. Our study will help an annual increment. to address this phenomenon of sex change and the View of a cross-section of a parrotfish ovary under the social dynamics involved by investigating the size/ Stock Assessment for O‘ahu microscope. Examining such age when individuals change sex as well as their Recently, our lab has completed an image can determine various aspects of parrotfish social behavior. field surveys to determine reproductive biology. the number, distribution and Movement and Behavior biomass of parrotfish around O‘ahu. We conducted Closely related to reproduction, the movement over 130 belt transects where parrotfish were and behavior of parrotfish will enable us to better counted, their lengths estimated, and the benthic understand sex change and social dynamics, as habitat quantified. The preliminary results of well as to determine how effective spatial fisheries this study suggest that parrotfish distribution management, like the implementation of Marine around O‘ahu is patchy, probably due to intense Protected Areas (MPAs) will impact these species. fishing activities and degraded habitat. Despite We have spent over four months working on the feeding on macroalgae, parrotfish seem to thrive Kona Coast of Hawai‘i to study the movement and in habitats that have high coral cover relative behavior of redlip parrotfish. The Kona Coast is to habitats that are primarily macroalgae and an ideal setting as it has fairly abundant and only turf-covered hard substrate. Although O‘ahu’s lightly fished parrotfish species. We have implanted largest MPA, Hanauma Bay, was not thoroughly Howard and a recently tagged parrotfish. acoustic tags in individuals to passively track these studied, our results do indicate that this area has a fish via underwater receivers. This technology disproportionately higher biomass of parrotfish than allows us to identify larger-ranging movements even the best quality habitats outside of Hanauma across the reef. We have also been tracking fish Bay. Combined with our recent behavioral and while snorkeling to look at both shorter range movement data, these findings are beginning movements and social behaviors. From what we to suggest that even modestly sized MPAs like have seen so far, redlip parrotfish seem to have Hanauma Bay may provide a good management very well-defined territories and the spawning option for parrotfish in Hawai‘i. observations we have made have all occurred within the male’s territory. The data collected in this study is intended to complement each other as well as the previous fish Age and Growth censuses that have been conducted Many fishery management models in the Hawaiian islands. It is our require some knowledge of age hope that this work will provide a and growth to be able to predict the solid framework for the effective stability of the population and the management of parrotfish in intensity of fishing pressure that this Hawai‘i, so that we can all continue population can withstand and still to enjoy the food, beauty and remain healthy. To accommodate these ecological benefits of these amazing needs, we have also been conducting reef fish. some age and growth research. We Howard have collected otoliths, fish ear bones, conducts a fish from fish of various sizes and from survey for her various locations around O‘ahu. When Kelly Boyle project.
15 Ka Pili Kai Na mea like ‘ole
John A. Knauss Marine Policy Fellowship
The John A. Knauss Marine Policy Fellowship provides a unique educational experience to students who have an interest in ocean, coastal and Great Lakes resources and in the national policy decisions affecting those resources. The program, which is sponsored by the National Oceanic and Atmospheric Administration's (NOAA) National Sea Grant College Program, matches highly qualified graduate students with "hosts" in the legislative and executive branches of government located in the Washington, D.C. area, for a one-year paid fellowship.
The length of assignment is one-year (non-renewable). The inclusive dates of the official fellowship each year are February 1st to January 31st. For further details visit the Knauss Marine Policy Fellowship Program website at: http://www.nsgo.seagrant.org/knauss/knauss.html
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