Hawaiian stream ecology as exemplified by the streams of the Kipahulu District, Haleakala National Park

Western Region, National Park Servic

Sponges and ascidians control removal of particulate organic nitrogen from coral reef water

10 pages, 5 figures, 5 tables.-- This is HIMB contribution 1199 and SOEST contribution 6596We studied removal rates of plankton and total particulate organic nitrogen (PON) by benthic reef communities from the overlying water in a large experimental flume. The flume was filled with mixtures of coral and coral rubble, and biomass of plankton was measured as water was recirculated over the experimental benthic community. All planktonic particle types, picoplankton, nanoplankton, microplankton, and total PON, decreased in concentration at rates proportional to their biomass. The mean first-order rate constant for the decrease in particle concentration was 96 ± 61 × 10-6 m s-1, corresponding to PON uptake of 10 mmol N m-2 d -1. Synechococcus sp. and heterotrophic bacteria were the major sources of PON. Particulate organic nitrogen removed by rubble and live coral assemblages was directly related to sponge and ascidian biomass (number and area) on the coral and coral rubble. Uptake of PON was about the same as the previously measured uptake of dissolved inorganic nitrogen into these coral reef communities, making it an important flux of nitrogen into the reef. © 2005, by the American Society of Limnology and Oceanography, Inc.Support for this work was provided by a postdoctoral fellowship from the Ministerio de Educación y Cultura (MEC) and a Ramón y Cajal research contract to M.R. This paper was funded in part by NOAA project R/CR-1, which is sponsored by the University of Hawaii Sea Grant College Program, School of Ocean and Earth Science Technology (SOEST), under grant NA 86RG0041. Additional funding was provided by CISNet (NOAA project NA 870A0531) and TransCom (Transfer at Community level) project (REN2002-01631/MAR)Peer Reviewe

Abrolhos Bank Reef Health Evaluated by Means of Water Quality, Microbial Diversity, Benthic Cover, and Fish Biomass Data

The health of the coral reefs of the Abrolhos Bank (southwestern Atlantic) was characterized with a holistic approach using measurements of four ecosystem components: (i) inorganic and organic nutrient concentrations, [1] fish biomass, [1] macroalgal and coral cover and (iv) microbial community composition and abundance. The possible benefits of protection from fishing were particularly evaluated by comparing sites with varying levels of protection. Two reefs within the well-enforced no-take area of the National Marine Park of Abrolhos (Parcel dos Abrolhos and California) were compared with two unprotected coastal reefs (Sebastião Gomes and Pedra de Leste) and one legally protected but poorly enforced coastal reef (the “paper park” of Timbebas Reef). The fish biomass was lower and the fleshy macroalgal cover was higher in the unprotected reefs compared with the protected areas. The unprotected and protected reefs had similar seawater chemistry. Lower vibrio CFU counts were observed in the fully protected area of California Reef. Metagenome analysis showed that the unprotected reefs had a higher abundance of archaeal and viral sequences and more bacterial pathogens, while the protected reefs had a higher abundance of genes related to photosynthesis. Similar to other reef systems in the world, there was evidence that reductions in the biomass of herbivorous fishes and the consequent increase in macroalgal cover in the Abrolhos Bank may be affecting microbial diversity and abundance. Through the integration of different types of ecological data, the present study showed that protection from fishing may lead to greater reef health. The data presented herein suggest that protected coral reefs have higher microbial diversity, with the most degraded reef (Sebastião Gomes) showing a marked reduction in microbial species richness. It is concluded that ecological conditions in unprotected reefs may promote the growth and rapid evolution of opportunistic microbial pathogens

The Ecology of the Replacement of Pseudosquilla ciliata (Fabricius) by Gonodactylus falcatus (Forskal) (Curstacea; Stomatopoda) Recently Introduced into the Hawaiian Islands

Volume: 22Start Page: 465End Page: 47

A limnological survey of lower Palikea and Pīpīwai streams, Kīpahulu, Maui

Reports were scanned in black and white at a resolution of 600 dots per inch and were converted to text using Adobe Paper Capture Plug-in.Since 1969, all of Kipahulu Valley above Palikea Peak, as well as Palikea Stream, have been part of Haleakala National Park. The "seven pools" area within 'Ohe'o Gulch has become a prime visitor destination, and continues to attract increasing numbers of tourists as well as island residents. The National Park Service is considering improvements in the 'Ohe'o-Pipiwai area which will accommodate existing visitor use levels, while maintaining the cultural and aesthetic integrity of the Kipahulu coastal area. These plans are discussed in the 55-page Draft Development Concept Plan for Haleakala National Park, Kipahulu District (NPS 1045) published in June 1976.National Park Service Contract No. CX 8000 6 003

Insect Introductions and Diet Changes in an Endemic Hawaiian Amphidromous Goby, Awaous stamineus (Pisces: Gobiidae)

Data are presented from gut content analysis of 94 Awaous stamineus (Edouyx & Souleyet) ('o'opu nakea) collected from the Wainiha River on the north shore of the Hawaiian island of Kaua'i during the period from June 1990 to May 1991. Also presented are results from gut analysis of 11 preserved museum specimens captured in La'iemalo'o stream, O'ahu, in February 1938 and June 1939. The results suggest that introductions of alien insects into the Hawaiian biota are changing the diet of this endemic fish. Comparison with the results of an earlier study indicate that A. stamineus is still dependent primarily on freshwater algae in the genera Cladophora, Rhizoclonium, Oedogonium, and Spirogyra; however, aquatic insect foods in the diet have increased from about 6% to nearly 13% in the current study. The findings suggest a reduced reliance on native aquatic chironomids in the genera Calospectra and Telmatogeton and an increased selection of immature stages of several recent aquatic insect immigrants, most notably two alien caddisfly species, Cheumatopsyche analis (Banks) (Tricoptera: Hydropsychidae) and Hydroptila arctia Ross (Tricoptera: Hydroptilidae), first reported in Hawai'i in 1967 and 1971, respectively

Temporal and spatial scaling of planktonic responses to nutrient inputs into a subtropical embayment

17 pages, 11 figures, 4 tablesWe carried out a study of the spatial and temporal effects of land-derived material on water column nutrients and plankton dynamics in a subtropical estuary. The study had 2 parts: (1) a 3 yr synoptic monitoring program, and (2) a shorter 1.5 yr study during the second half of the program, which focused on individual pulses driven by discrete rainfall events. Although we found spatial differences in some water column parameters within Kane'ohe Bay and an adjacent oceanic site, inorganic nutrient levels were generally comparable in the Bay and offshore. One difference was that Prochlorococcus spp. numerically dominated the plankton at the oceanic site whereas Synechococcus spp. dominated at all Bay sites. The switch in dominance appears to be due to light characteristics and dissolved organic nitrogen (DON), but not dissolved inorganic nutrient availability. There were no annual cycles in water column parameters within the Bay; however, a comparison of dry and wet seasons did show some differences. Planktonic cell abundance was in general lower during the wet season, with the exception of opportunistic diatoms that were more abundant during the wet season. A drought during the study period may have influenced our results. Pulses were characterized by an elevation in inorganic nutrient concentrations in the Bay close to the stream mouth. The general response was an increase in abundance of microphytoplankton and chl a after a 3 to 6 d lag following the nutrient increase. Picophytoplankton showed an increase in fluorescence per cell after a 12 to 24 h lag, probably related to a decrease in irradiance associated with turbidity in runoff. The Bay can act as source of dissolved inorganic nutrients and plankton for oceanic waters; however, planktonic populations in the Bay are primarily autochthonous and do not represent an oceanic source of nutrients for plankton consumers within Kane'ohe Bay.This paper was partially funded by NOAA: CISNet (NOAA project NA 870A0531) and University of Hawai'i Sea Grant Project NA36RG0507. Support for this work was provided by a Postdoctoral Fellowship from the ‘Ministerio de Educación y Cultura, MEC’ and a RyC research contract to M.R. Additional funding was provided to M.R. by TRANSCOM project (REN2002-01631/MAR).Peer reviewe

WRRCTR No.147 Population Biology in Small Hawaiian Streams

Intensive stream surveys were conducted on Maui and Kauai in Hawaiian island streams during October 1979 through 1982 to investigate whether the presence of predaceous eleotrids in terminal reaches of low-gradient streams excluded the rare goby, Lentipes concolor, from this habitat and restricted it to higher elevations. An attempt was also made to determine whether a correlation exists between seasonality of stream discharge patterns and the two life history parameters (spawning and recruitment) of the indigenous, diadromous species. Two small perennial streams, Puaaluu and Pepeiaolepo, on the island of Maui, and another small stream, Maunapuluo, on the precipitous Na Pali Coast of Kauai were selected as study areas. Although evidence indicated that Eleotris sandwicensis preys upon gobies and rarely coexists with Lentipes, many other factors influence the effectiveness of Eleotris as a predator. Factors affecting the distribution and abundance of Lentipes are complex. No sharply defined periodicity was found in the recruitment of diadromous fishes, crustaceans, or mollusks. In-stream factors, among-stream and among-island differences in physical and biotic parameters apparently make recruitment into small Hawaiian streams an event in which chance plays a dominant role. In larger streams these stochastic processes may be averaged out and populations of these indigenous animals are more stable. The importance of these physical, biotic factors in determining the disturbance of populations of native stream fauna is discussed.Office of Water Policy, U.S. Department of the Interior Grant/Contract No. 14-34-0001-1113; A-080-H

Particle removal by coral reef communities: picoplankton is a major source of nitrogen

Este artículo contiene 11 páginas, 5 figuras, 4 tablas.Removal and uptake of planktonic particulate organic matter by coral reef benthos is widely recognized as an important pathway for carbon and nutrients. We placed 3 natural assemblages of coral reef benthos, including 3 species of corals with associated sponges, ascidians, actinians, and bryozoans, in a long flume (24 × 0.4 × 0.3 m). Water was re-circulated at various speeds (5, 13, 22, and 32 cm s–1) over 6 h, and the disappearance of particles (pico-, nano-, microplankton and detrital particles) were measured using flow cytometry and microscopy. Control communities consisted of dead coral skeletons. Rates of removal of all particles were proportional to their concentrations. The first-order rate constant for the decrease in particle concentration ranged from 36 to 97 × 10–6 m s–1 (mean ± SD = 63 ± 16 × 10–6 m s–1), with 71% of this variation explained by particle type. Water velocity had no significant effect on these rate constants. Living particles contributed 96% of the total nitrogen removal, with picoplankton (cells 0.2 to 2 µm) accounting for 92%. Overall, nitrogen removal from particles (8.8 to 10.3 mmol N m–2 d–1) appears to be similar in magnitude to that of dissolved inorganic nitrogen; thus, picoplankton is a major source of nitrogen for these coral reef assemblages.This paper was funded in part by the NOAA project #R/CR-1, which is sponsored by the University of Hawaii Sea Grant College Program, SOEST, under Grant #NA 86RG0041. Additional funding was provided by CISNet (NOAA project #NA 870A0531).Peer reviewe

WRRCTR No.171 Habitat modelling of Hawaiian streams

Department of Land and Natural Resources Division of Water and Land Development Grant/Contract No. 16732,17566An evaluation of the Instream Flow Incremental Methodology (IFIM) was carried out to assess the applicability of this technique to Hawaiian streams. Hydraulic simulations were made for two study reaches on Nanue Stream, Hawaii, and one study reach on Wainiha River, Kauai. Four simulations were carried out and compared: WSP used alone, IFG4 using several data sets, WSP and IFG4 in combination, and IFG4 using only a single data set. Habitat utilization and preference were determined for three stream gobies, Awaous stamineus, Sicyopterus stimpsoni, and Lentipes concolor. IFIM was used with habitat data for S. stimpsoni to determine weighted usable area and to carry out time series analyses for Wainiha River. Results of the hydraulic simulations indicate that IFG4 using several data sets yields the best simulation of stream hydraulics. The WSP simulation program does not appear to be suitable for many Hawaiian streams, particularly smaller streams or streams with complex channels. The habitat utilization studies indicated that the three species used available habitat in different ways giving rise to some microhabitat differentiation. Tests were also made to determine if habitat preference curves derived from fish in one stream could be transferred to another stream. Tests of transferability indicated that habitat utilization data collected from one stream could not be reliably transferred to another stream. Finally it was concluded that IFIM is suitable for certain Hawaiian conditions provided that appropriate precautions in project design, data collection, and simulation studies are taken