Two new monitoring approaches: (i) 'Resource-Fish' surveys (targeting the large and mobile fishes which are primary targets of recreational and commercial food fisheries); and (ii) 'Benthic Characterization' (intended to be a medium-large scale survey approach capable of relatively easily generating benthic information suitable for improved understanding of fish distribution and community structure, and for detecting gross change in benthos) were developed and field trialed at sites in West Hawaii.
Extended fish trials of an 'integrated monitoring' approach, comprising both existing small-scale and the newly developed medium-large scale approaches were conducted at 14 sites in West Hawaii (Big Island) (each site surveyed 4 times for fish, once for 'Benthic Characterization'). Additionally, 'Resource-Fish' surveys using the newly developed methodology were conducted at 39 sites in Maui, and data from those surveys compared with an alternative approach focusing on the same fish groups which had been previously utilized at Maui sites (but not elsewhere in the state). 'Benthic Characterization' surveys were conducted at 14 sites in West Hawaii.
This dataset includes only the 'Resource-Fish' surveys. The 'Benthic Characterization' sets will be provided to the NOAA posterity archive at a later date. NODC Accession Number 0002627 contains the same data in this dataset for West Hawaii. This new dataset adds the Maui 'Resource-Fish' data.
Overview and Objectives: Pairs of divers conduct 5 or 7 minute timed swims recording the number of all medium-large (>15cm TL on Big Island; >10cm TL on Maui) "resource fishes" (Table 1). Divers aim to cover moderate to large areas while looking as far ahead as possible so that diver-observers can focus on the large, mobile and sometimes skittish fishes which are the principal targets of commercial and recreational food fisheries.
Detail: Divers work in pairs, starting from a fixed central point in the survey site (e.g. central pins of WHAP H formation). Divers swim outward from the starting point following the depth contour and remaining where possible within a contiguous stretch of habitat. Divers should aim to move steadily, and adjust their own speeds to prevailing currents so that total distance covered is around 120-150m per 5-minute survey. In West Hawaii, most survey sites are aligned roughly N-S, so one pair of divers swim approximately north and one pair south. Each diver records the size and number of "resource fishes" with total length larger than 15cm within a 5m-wide swath centered on themselves. One diver in each pair will either tow a surface float with a tracking GPS, or deploy a buoy at the end of the swim, so that distance covered per survey can also be calculated (and therefore counts can be analyzed on a per-time or per-distance basis). Data from a pair of divers will always be pooled prior to analysis and therefore, divers should strive not to double count fishes (e.g. a fish moving across the field of vision of both divers should only be counted one of the pair, normally the diver from which side the fish started). Fish sizes are to be recorded in 5cm-slot size categories: D = 15-20 cm; E = 20-25 cm; and fishes larger than 25cm recorded to nearest 5 cm.
In West Hawaii, transects are laid out in an H pattern and are labeled from A to D: transects A and C run parallel, approximately 10m apart and heading northwards from the central pin following the depth contour. B and D transects are also 10m apart and parallel, but run southwards. Mid-depth of each site is around 40ft.
Maui sites are aligned parallel to shore- sites are either shallow (~10ft) or deep (~35ft).
Filename comment a) TimedSwim Methods for PatCaldwel incl MAUIl.doc description b) Williams TimedSwim Data 2005 incl Maui.xls data
2. Directory data/nodc These files have had filename standardization.
a) above was renamed TimedSwimMauiWHawFshRsrc.doc. It was dumped into a redundant PDF (TimedSwimMauiWHawFshRsrc.pdf) and ASCII Text (TimedSwimMauiWHawFshRsrc.txt). Note in the later, the tables become difficult to understand. Figures and Tables from this document were saved to separate files as
Filename comment MauiLocations.jpg map WHawLocations.jpg map TimedSwimMauiWHawFshRsrc_Table01.jpg Resource Fish TimedSwimMauiWHawFshRsrc_Table02.jpg Sample Log Sheet TimedSwimMauiWHawFshRsrc_Table03.jpg Big Island names/coordinates TimedSwimMauiWHawFshRsrc_Table04.jpg Maui names/coordinates
Original data file received in MS Excel, b) above, was renamed to TimedSwimMauiWHawFshRsrc.xls. Then, each sheet of this spreadsheet was dumped into a redundant Comma-Separated Version (CSV) ASCII files,
The files are self-descriptive.