Arrows represent the flow of fish within the supply chain, while stars represent possible intervention points these interventions can occur at the production level (1) e.g. restrictions on fishing activity; distribution level (3) e.g. tracking trading between distributors; consumption level (5) e.g. influencing consumer demand for sustainably caught fish, or at linkages between steps.

<p>These linkages include transport to market (2) e.g. improving communication or tracking of fish flows, and the final transport to consumers (4) e.g. mandating reporting for off island shipments.</p

Value chain of nearshore fish in Hawaiʻi.

<p>Dark blue arrows represent quantified flows while light blue arrows indicate flows of unknown quantity. Known flows are considered to be underestimates and are nested within larger light blue unknown flows. Production comes from non-commercial and commercial fisheries, with some imports. The non-commercial local fishery largely supplies non-commercial consumption and sharing. Commercial catch derives from both licensed and non-licensed fishers. Only licensed fishers are required to report catch to state officials. Most (at least 62%) of the licensed catch stays in the formal market, and was sold to dealers, who voluntarily report their purchases entering commercial markets directly from fishers. Dealers also trade an undisclosed amount between each other. An unknown amount of nearshore fish is exported from Hawaiʻi. Both the commercial and non-commercial sectors add value to the economy.</p

Follow that fish: Uncovering the hidden blue economy in coral reef fisheries

<div><p>Despite their importance for human well-being, nearshore fisheries are often data poor, undervalued, and underappreciated in policy and development programs. We assess the value chain for nearshore Hawaiian coral reef fisheries, mapping post-catch distribution and disposition, and quantifying associated monetary, food security, and cultural values. We estimate that the total annual value of the nearshore fishery in Hawaiʻi is $10.3-$16.4 million, composed of non-commercial ($7.2-$12.9 million) and commercial ($2.97 million licensed +$148,500-$445,500 unlicensed) catch. Hawaii’s nearshore fisheries provide >7 million meals annually, with most (>5 million) from the non-commercial sector. Over a third (36%) of meals were planktivores, 26% piscivores, 21% primary consumers, and 18% secondary consumers. Only 62% of licensed commercial catch is accounted for in purchase reports, leaving 38% of landings unreported in sales. Value chains are complex, with major buyers for the commercial fishery including grocery stores (66%), retailers (19%), wholesalers (14%), and restaurants (<1%), who also trade and sell amongst themselves. The bulk of total nearshore catch (72–74%) follows a short value chain, with non-commercial fishers keeping catch for household consumption or community sharing. A small amount (~37,000kg) of reef fish—the equivalent of 1.8% of local catch—is imported annually into Hawaiʻi, 23,000kg of which arrives as passenger luggage on commercial flights from Micronesia. Evidence of exports to the US mainland exists, but is unquantifiable given existing data. Hawaiian nearshore fisheries support fundamental cultural values including subsistence, activity, traditional knowledge, and social cohesion. These small-scale coral reef fisheries provide large-scale benefits to the economy, food security, and cultural practices of Hawaiʻi, underscoring the need for sustainable management. This research highlights the value of information on the value chain for small-scale production systems, making the hidden economy of these fisheries visible and illuminating a range of conservation interventions applicable to Hawaiʻi and beyond.</p></div

Description of fish dealer categories according to Hawai‘i DAR.

<p>Description of fish dealer categories according to Hawai‘i DAR.</p

Cultural values, definitions, and evidence in Hawaii.

<p>Cultural values, definitions, and evidence in Hawaii.</p

Trophic group breakdowns for commercial and non-commercial catch, by value-added at the fisher level, and additional value-added by commercial fish dealers.

<p>Dark gray box demarcates the non-commercial catch and value-added; light gray the commercial catch (value-added derived from fishers and dealers).</p

Estimating nearshore coral reef-associated fisheries production from the main Hawaiian Islands

<div><p>Currently, information on nearshore reef-associated fisheries is frequently disparate or incomplete, creating a challenge for effective management. This study utilized an existing non-commercial fishery dataset from Hawaiʻi, covering the period 2004–13, to estimate a variety of fundamental fishery parameters, including participation, effort, gear use, and catch per unit effort. We then used those data to reconstruct total catches per island. Non-commercial fisheries in this case comprise recreational, subsistence, and cultural harvest, which may be exchanged, but are not sold. By combining those data with reported commercial catch data, we estimated annual catch of nearshore reef-associated fisheries in the main Hawaiian Islands over the study period to be 1,167,758 ± 43,059 kg year^-1 (mean ± standard error). Average annual commercial reef fish catch over the same time period—184,911 kg year^-1—was 16% of the total catch, but that proportion varied greatly among islands, ranging from 23% on Oʻahu to 5% on Molokaʻi. These results emphasize the importance of reef fishing in Hawaiʻi for reasons beyond commerce, such as food security and cultural practice, and highlight the large differences in fishing practices across the Hawaiian Islands.</p></div

Recreational CPUE per island, platform, and gear.

<p>Data shown are mean and standard error (SE) of CPUE by island for each combination of island, platform, and gear in intercept surveys by MRIP between 2004–13. Eqs <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0195840#pone.0195840.e003" target="_blank">3</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0195840#pone.0195840.e006" target="_blank">4</a> were used to calculate mean and variance of CPUE values. Reef fishes are taxa as defined in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0195840#pone.0195840.s001" target="_blank">S1 Table</a>. Note that as there were no intercept surveys on Lānaʻi, CPUE data for there are assumed to be the average from other islands. Lānaʻi CPUE SE was generated using the average precision (SE/mean) from all other islands. The number of catch interviews per combination of island, platform, and gear is given in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0195840#pone.0195840.s003" target="_blank">S3 Table</a>.</p

Recreational fishing effort.

<p>Data come from MRIP telephone surveys in 2004–2013. Data are summarized as mean and standard deviation of values per wave (i.e., for the 60 2-month periods in that 10-year period). Participation rate is proportion of households in which someone fished in the preceding wave; trips per household represents the number of fishing trips per fishing household in that period. Total # trips was calculated using <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0195840#pone.0195840.e001" target="_blank">Eq 1</a>. Number of households ranged from 63,209 to 64,909 for Hawaiʻi Island, 21,968 to 22,390 for Kauaʻi, 1,068 to 1,074 for Lānaʻi, 43,505 to 49,080 for Maui, 2,525 to 2,561 for Molokaʻi, and 303,794 to 309,803 for Oʻahu.</p

Recreational trip types.

<p>Data come from MRIP telephone surveys in 2004–2013. Data are summarized as mean and standard deviation per island and wave of the percentages of fishing trips per combination of platform (boat or shore) and gear as defined by <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0195840#pone.0195840.e002" target="_blank">Eq 2</a>. Gears have been pooled into line, net, spear, or not-reef (offshore, pelagic or bottomfish fishing), as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0195840#pone.0195840.s002" target="_blank">S2 Table</a>.</p