An Overview of Guam's Inshore Fisheries

REBECCA A. HENSLEY and TIMOTHY S. SHERWOOD

Introduction families or shared with the community Mariana Island Archipelago with over and were harvested from three main 130,000 people on about 550 km2. Background areas of the sea: The coral or nearshore Much of the change in Guam's fisher­ shallow adjacent areas, nearshore ies, from traditional subsistence fish­ Since long before the first contact of westerners with native Guamanians (or slopes to about 100 fathoms and the eries to the more modem subsistence, surface ocean waters. Much of the tra­ commercial, and recreational fisheries Chamorus 1) in 1521, fish has been the ditional use of fish for social obliga­ has occurred since World War II. primary source of protein for the is­ landers. Little is known about tradi­ tions in the form of fiestas (large Johannes (1978) maintained that the gatherings for funerals, weddings, tional management of Guam's decline.of the Pacific island fisheries christenings) is still practiced. was due mostly to change in the eco­ fisheries, but fishing was and has re­ mained an important part of life and Guam is a U.S. territory located in nomic system of the Pacific Islands to culture. In the past, subsistence fishing the western Pacific (Fig. 1). It is the a more western one which has eroded southernmost and largest island in the the ancient marine tenure laws and tra­ provided Guam's residents with an ample supply of fish. Most of the fish caught were consumed by fishermen's .NJUG-1-20 IChamoru, previously Chamorro, is the cur­ rently accepted spelling of the indigenous people of Guam. . , The authors are with the Division of Aquatic and Wildlife Resources, Government of Guam, P.O. Box 2950, Agana, Guam 96910. Corre­ spondence to them may be addressed as fol­ lows: R. A. Hensley, Texas Parks and Wildlife . Department, 1231 Agnes St., Corpus Christi, TX 7840 I; and T. S. Sherwood, 3245 Austin Dr., Colorado Springs, CO 80909. Views of ~ SAIPAN IS" opinions expressed or implied are those of the authors and do not necessarily represent the ., position of the National Marine Fisheries Ser­ vice, NOAA. GUiMI

ABSTRACT-Guam's nearshore reef fishery is a multi-gear, multispecies fish­ ery that has undergone major changes through the years. Methods have evolved and become more modern. This, along with the changing economic status of Guam, has severely stressed the fishery. Top tar­ geted species are being overexploited and "growth overharvesting" is occurring; the more serious form of "recruitment over­ harvesting, .. is happening to some of the key species. Major management concerns are discussed with respect to overfishing and habitat destruction. Management rec­ ommendationsfor thisfishery include gear restrictions, size restrictions, and the es­ Figure I.-Guam (l3"30'N; 144"50'E) is the southernmost of the tablishment ofmarine conservation areas. Mariana Archipelago.

55(2), 1993 129 ditional island conservation ethics. Guam's Inshore Fisheries portions going to the owner of the net, This, along with the introduction of the village where the fish were caught, more modern, manufactured fishing Historic Fishing Methods and those who helped harvest the catch. materials (monofilament nets, steel hooks, poles, reels, spearguns, scuba Detailed fishing techniques from Contemporary Fishing Methods gear, etc.), has changed the complex­ prehistoric times have been described ion ofGuam's inshore fishery and aided by Amesbury et al. (1986) and will be Many of the currently used methods in the decline of the nearshore reef only briefly described here. Early fish­ are very efficient because the technol­ fishery. Ikehara et a!. (1970) stated that ing techniques (prior to the 1930-40 ogy and materials used are readily Guam's shallow inner reefs appeared period) employed gear composed of available at a minimal cost. Contem­ to be fully exploited and showed signs natural materials. Today, inshore (or porary methods include hook and line, of overfishing. Katnik (1982) found reef and lagoon) methods have incor­ net fishing (cast, gill, drag, and sur­ that two heavily fished areas on Guam porated modern equipment and have round net), spear fishing (snorkel and were overfished and stated that other been modified in some manner from scuba), hook and gaff, and "other" accessible areas on Guam could be the traditional form of fishing. Some methods (a miscellaneous category that equally overexploited. What was once form of hook and line fishing, usually includes mostly gleaning for inverte­ a well stocked, complex fishery with handline, has been done since the ar­ brates). These methods, modified diverse fishing methods has changed rival of the Chamorus on Guam around through time, are described below and to a fishery under serious fishing 1500 BC (Amesbury et a!., 1986). Net account for the harvest of over 100 pressure. fishing has included forms of dip net­ species of finfish and 40 nonfinfish ting, bag seining, throw netting, sur­ species (3 lobster, 9 crab, 24 mollusk, Scope round netting, drag netting, and gill and 4 echinoderm? (Amesbury et a!., Because of the increased efficiency netting (a more recent form of net fish­ 1986,1991). of fishing techniques due to introduc­ ing). Fishing with traps and spears has Currently, the most popular fishing tion of modern materials and because occurred throughout the history of method on Guam is hook and line. This of the increase in fishermen and the Guam. Women historically harvested technique ranges from the use of island population, the Guam Division the seagrass parrotfish (Scaridae) and handlines to rod and reel with lures or of Aquatic and Wildlife Resources some wrasses (Labridae) by hand. All baited hooks. Recently, we have ob­ (DAWR) recognized the need to pro­ social classes of Chamorus harvested served fly fishing in Guam's waters. tect the fishery from overharvesting. eels with iron spears and crabs with The majority of the fish harvested Initial monitoring of the resources be­ multipronged spears. Gleaning for in­ are taken by net fishing. All types of gan in the 1960's, and it had evolved vertebrates has always occurred, espe­ net fishing done today, except gill net­ by 1982 into the current creel survey cially for mollusks and algae for use as ting, have long histories on Guam. Net methodology adapted from Malvestuto either bait or food. The Spaniards mesh sizes range from 1/4-inch stretch et al. (1978). Because of the different gleaned for sea cucumbers. (for seasonal juveniles) to greater than usage and the different areas of the sea Several types of fishing no longer 3-inch stretch. The cast net or throw utilized for the multispecies, multigear occur. Two of these are the opelu or net (talaya) is one of the few nets that fisheries, Guam's fisheries monitoring hachuman fishing (for Decapterus sp.) are still hand woven (using mono­ filament) by the traditional talaya fish­ was divided into two projects. These and the decoy method of fishing 3 were the "inshore" (or nearshore reef) (Amesbury et a!., 1986). Turtles were ermen . These nets vary in mesh size fisheries and the "offshore" (small harvested until 1976 when it was pro­ and number of pockets depending on boat) fisheries (Myers, 1993). The in­ hibited. Other currently prohibited the fish targeted. shore fisheries discussed here will en­ methods include fish weirs, fish poi­ Other than the modem equipment, compass the coral or nearshore shallow soning from root extract (Barringtonia drag netting has changed very little adjacent waters which consists mostly asiatica tree), chlorine bleaching, and through time. It still is the simplest of fringe reefs. dynamiting. These are still practiced form of net fishing where the net is This paper describes inshore fisher­ illegally on a small scale. ies, concentrating on data from 1982 Traditional fishing practices are still 2This identifies all information, unless other­ through 1991. We discuss fishing tech­ observed routinely on Guam. One prac­ wise cited, obtained by the authors from Guam Fisheries Investigations-Project FW-2R-26 Job niques and data collection and compi­ tice is the fishing for seasonal juve­ Progress Reports (Jobs: F-FI-2 Inshore Fisher­ lation for landing and effort estimates niles recruiting to the reef flats ies Survey; F-FI-3 Fisheries Data Processing; of Guam's fishery. The harvest com­ (discussed below), while the other prac­ F-FI-8 Studies of Recreationally Important Reef Fish). Information can be obtained from ponents (finfish, nonfinfish, and sea­ tice involves sharing the catch. The the Division of Aquatic & Wildlife Resources sonal juveniles or traditional fishery) catch from the surround net or chen­ (DAWR), Dept. of Agriculture, P.O. Box 2950, and current management practices are chulu (when used for catching seasonal Agana, Guam 96910. 3D. Narcissi, Talaya fisherman, Guam Envi­ described with suggestions for conser­ mackerel or Selar crumenopthalmus) ronmental Protection Agency, Harmon, Guam vation of the fishery. is still divided up into thirds with the 96912. Personal commun.

130 Marine Fisheries Review pulled through the water as the fish are or little-used techniques like dip net­ records all active fishing participation driven into the net. Today, this method is ting and mantis shrimp traps fall into (time of day, location, number of most often, but not always, used at night. this miscellaneous category. people, number of gear units, fishing The use of the surround net or chen­ methods, reef zone fished, weather con­ Inshore Creel Survey chulu has occurred for many years. ditions, and surf conditions). Counts Today, two types of surround netting The primary objective of the inshore are made of fishermen and gear and occurs. In the first type, two people fisheries survey was to obtain the most are used to estimate effort in terms of transport the net through the water on accurate estimate of the total annual person-hours (p-hr) and gear-hours (g­ two large inner tubes. The fishermen inshore fisheries harvest in order to hr). The catch survey is of the roving begin setting the net in a 'u' shape and monitor and manage the resource. Fish­ fisherman-intercept type and requires close the net into a circle as a second ing activity has been monitored since as many interviews for as many fish­ group of people drive the fish into the the early 1960's when much of the ing methods as possible. The survey net. Once the net is set, the fishermen early information was taken by DAWR variables collected include fishing dive into the enclosure and harvest the conservation officers (law enforcement method, number of fishermen, bait fish by spear and/or hand. The second personnel). Monitoring changed over type, number of gear, mesh size, inter­ form of the surround net, also called the years, as did fish identification. view time, trip length, species caught, the atulai gill net (Amesbury et a!., The early 1960's catch was identified numbers of catch species, and indi­ 1986), is one that is used to harvest by the Chamoru name of the fish. Prob­ vidual weights and lengths. Catch data seasonal macker~1 or atu1ai. This net is lems with catch composition arose be­ is used to estimate overall landings (kg), most commonly used in the harbors, cause one name could mean any wrasse CPUE, and species composition. channels, or bays. When a school of species, parrotfish would be identified The majority of the species caught atulai is sighted, a boat surrounds the by color (blue, brown, white, and are represented with this methodology. fish with the net and the school can be green), and rabbitfish would be identi­ Species that recruit en masse, like harvested over a period of days. fied by at least five names that de­ mafiahak (rabbitfish) or atulai, cannot Gill net fishing is the most recent scribed the fish by size. As taxonomic be adequately represented in the cur­ form of net fishing on Guam. This skill increased, the catch was reported rent creel survey. Catch estimates of method is very popular (usually rank­ in increasing detail. these species are obtained when the ing in the top three of all methods used). Working closely with the U.S. Na­ recruiting runs occur and are added to This popularity is due to the availabil­ tional Marine Fisheries Service, the the survey expansion catch values to ity of the gill nets, the comparative DAWR developed a program for ana­ obtain the yearly inshore harvest. lyzing the inshore fisheries. Since the low cost, and the effectiveness of the Finfish modem monofilament materials. The installation, all the data collected has net is used at any time of the day or been analyzed by this program. In 1991, Finfish are the primary harvest (usu­ night, but it is most successful on an we modified and restructured our analy­ ally >95%) of contemporary fishing ebb tide where fish escaping the shal­ sis to allow comparison of data from methods. This harvest includes all sizes lows are gilled in the net. 1982 to the present. (Because of method­ of reef fish, even the highly antici­ Spearfishing has undergone a vast ological changes, data prior to 1982 do pated seasonal runs of juveniles. change with the advent of modern not lend themselves to analyses.) Deepwater and/or pelagic fish, nor­ equipment, evolving from handmade Survey Methodology mally harvested using offshore tech­ spears and freediving to spearfishing niques, are occasionally caught using with scuba gear. Spearfishing with Because much of the shoreline is inshore methods. Over 100 species of snorkel and spearfishing with scuba inaccessible to most fishermen (Le., finfish are harvested in the inshore fish­ target different fishes and are consid­ military bases, clifflines), not all of ery. The primary families include: ered separate techniques. Because of Guam is surveyed. Data collection for Acanthuridae, Carangidae, Gerreidae, the highly selective nature of both of the inshore fisheries expansion is con­ Holocentridae, Kyphosidae, Labridae, these methods, spearfishing harvest ducted in an area representing 85% of Lethrinidae, Lutjanidae, Mugi1idae, consists of fish of larger species (i.e., the total fishing participation (verified Mullidae, Scaridae, and Siganidae. The humphead parrotfish, BoLbometopon from shoreline usage seen during aerial top ten species caught in the inshore muncatum) than other fishing techniques. surveys). A two-part roving creel sur­ fishery, not including seasonal juve­ The remaining two methods are pri­ vey, effort (or participation) and catch, niles, are Naso unicornis, Caranx marily used for harvesting nonfinfish. is performed for both day and night meLampygus, Siganus spinus, MuL­ The use of hooks and gaffs targets oc­ (begun in 1985) to provide sufficient Loides flavoLineatus, Lethrinus harak, topus, although some mantis shrimp data to allow for 90% confidence lim­ VaLamugiL engeLi, Kyphosus cineras­ and miscellaneous fish are also caught. its for the inshore analysis. Detailed cens, K. vaigiensis, CheiLinus!asciatus, The last method, a catch-all category methodology and analyses are de­ and Gerres sp. Ranking of these spe­ appropriately called "other," generally scribed in Amesbury et a!. (1991). cies changes as fishing pressure and includes gleaning for nonfinfish. New During an effort survey, a surveyor gear use fluctuates.

55(2), 1993 131 The harvest of one of these key spe­ The harvest of recruiting juvenile shore waters by the age of 4 months cies, Mulloides flavolineatus, best de­ fishes (Table 1) makes up Guam's tra­ (Amesbury et aI., 1986). The atulai are scribes what is occuring in the finfish ditional finfish fishery. It historically harvested with surround nets, cast nets, fisheries. By 1991, the harvest declined has been and still remains an impor­ and by hook and line and usually rep­ by 90% over a 6-year period (from tant part of the nearshore reef fisher­ resent the majority of the seasonal 33,896 to 3,417 kg). The 100-150 mm ies. Seasonaljuvenile harvest can range harvest. size class is targeted in the traditional from a minor component of < I% (in The recruitment of other juveniles, fishery, which prevents many fish from 1982-83) to over 50% of the overall like i'e' (jacks), ti'ao (goatfish), en reaching larger size classes and further harvest (in 1991). masse and aguas (mullet), do not occur impacts the reproductive potential of Two major components of the juve­ like the mafiahak or atulai, but they are the population. The downward trend nile harvest are mafiahak and atulai still heavily fished. The recruitment in overall harvest is characterized by (Fig. 2). The local residents anxiously periods for these juvenile fishes often the absence of larger females that rep­ await the recruitment of both species overlap and peak harvests are seen ev­ resent the major portion of the spawn­ to the nearshore reef waters. Even ery 3-4 years. The harvest of these ing potential. though the yearly run of mafiahak does juveniles is primarily by net fishing Many of the once economically im­ not always occur, fishermen will gather portant larger species, like the at the shoreline during the first few humphead parrotfish, Bolbometopon days of the last quarter lunar phase of Table 1.-Seasonal juvenile fishes targeted in Guam's traditional finfish fishery. Chamoru names muricatum; wrasse, Cheilinus undu­ the expected recruitment period. The are after Kerr (1990). latus; groupers over 25 kg, and snap­ mafiahak recruit onto the flat area of (English Name) pers are rarely seen in Guam's waters, the reef in aggregations or "balls", as Chamoru name Family and species targeted much less reported on the inshore sur­ they undergo morphological develop­ Aguas (mullet) Mugilidae vey catch reports. Interest in the har­ ment from planktivorous to herbivo­ Alulai (bigeye Carangidae; Sefar vest of aquarium fish is on the rise, rous fish (Kami and Ikehara, 1976). scad, mackerel) crumenopthalmus Achemsom' while the actual harvest appears to be The largest, as well as the most eco­ (fusilier) Caesionidae declining. These fish may be less sus­ nomically valuable, catch of mafiahak I'e' (jacks) Carangidae; ceptible to overfishing because of their is prior to the complete coloration and primarily Caranx meJampygus Mafiahak Siganidae; Siganu5 spinus, high turnover rate, but problems are dietary change (the first 1-2 days on (rabbitfish) S. argenteus beginning to surface with respect to the reef). Harvesting of mafiahak is Ti'ao (goatfish) Mullidae; Mulloides flavolineatus the use of chemicals for fish collect­ conducted with all nets using a '/4_ 1 Many local fishermen use this name to incorrectly ing, habitat destruction, and unmon­ 'h inch stretch mesh size. Atulai usu­ identify juvenile fusiliers when they recruit en masse. Achemsom actually means small rainbow runner itored or illegal catches. ally begin their seasonal runs into in­ (Carangidae; primarily Elegatis bipinnufatus) .

• Manahak (kgs) 0 Atulal (kgs)

40,000 80,000

35,000 70,000 ~ VI 01 ~ VI ~ 30,000 60,000 01 ... ~ .,VI 25,000 ... ~ 50,000 .,VI :I:'" ~ .>< 20,000 40,000 :I:'" ~'" .; c'" 15,000 30,000 "5... ~'" < 10,000 20,000

5,000 10,000

0 0 FY82 FY83 FY84 FY8s FY86 FY87 FY88 FY89 FY90 FY91 SURVEY PERIOD

Figure 2.-Estimated harvest from 1982 through 1991 of two of Guam's seasonal juveniles (maiiahak = young rabbitfish, primarily Siganus spinus; atulai = young mackerel, Selar crumenoplhalmus; FY = 12­ month fiscal year). Names are after Kerr (1990).

132 Marine Fisheries Review (using 1/4-1/2 inch stretch mesh size), mollusk; squid and cuttlefish form part legally until 1976. Inshore catch re­ except the i'e' which are often har­ of the incidental catch. Of all these, ports for 1967-68 noted landings of vested by hook and line. only Trochus has a fisheries potential over 80 turtles in 18 months, the larg­ and is currently regulated with size re­ est individuals weighing an estimated Nonfinfish strictions and is strictly monitored. 450 pounds. It is currently difficult to Until recently, the funding con­ Crustaceans make up a major por­ determine the extent of the actual catch strained the DAWR to work on fin­ tion of the nonfinfish catch. About nine because of the illegal nature of this fishes only; therefore, information on species of crab are hunted, including activity. Examples of significant poach­ nonfinfish is limited to catch statistics land and marine crabs. Carpi/us ing activities were seen during a 2­ for methods that also target finfish. maculatus (7-11 crab) and Etisus week period in 1990-91, when an Since harvesting of invertebrates is one splendens are primarily targeted, estimated 20 turtles (in two separate of the less frequent and easily missed whereas Calappa hepatica and rarely incidents) were poached. activities (i.e., virtually all lobsters are C. calappa (box crabs) are taken as Catch and Effort Estimates taken by spearfishing), our nonfinfish incidental catch during net fishing, harvest is probably underestimated. For spearfishing, or gleaning. Two species Overall catch values for 1982-91 a few of the species most often col­ of land crabs (Cardisoma carnifex and for all fish caught (finfish, nonfinfish, lected, the true annual catch is prob­ Birgus latro) are also highly prized, and seasonals) for both day and night ably only a few metric tons at most. but are not monitored on the inshore are shown in Figure 3. In 1990, the The coral reef is Guam's single most fisheries surveys. Lobster catches are participation declined to less than 50% valuable resource, and, over the years, highly prized. The following species (42,294 fishermen) of the 1984 high coral has been harvested for ornamen­ are identified in Guam's catches: (107,391 fishermen). Similar trends for tal and commercial use. The most com­ Palinuridae (Panulirus longipes, P. effort and catch are seen (Fig. 3) where mon corals harvested commercially in ornatus, P. pencillatus, P. versicolor), the highs occurred in 1984, but lows the past included Acropora, Antipathes, Homaridae, and Scyllaridae. The spiny occurred in 1989 and 1990. Effort and Fungia, Heliopora. and Tubipora sp. lobster, primarily P. pencillatus and participation increased in 1991 and are (Hedlund, 1977). Coral (dead or live) the slipper lobster, Scyllarides squa­ attributed to an excellent year for sea­ is no longer legally collected without a mosus, are the two main components sonal juvenile harvest. If harvest esti­ permit (now issued for educational or of the inshore lobster catch and are mates for atulai and mafiahak (Fig. 2) research purposes only), and the regu­ harvested by spearfishing and "other" were removed from the catch values, lation is strictly enforced. techniques (i.e., gleaning). Mantis shrimp, the overall harvest falls between 1989 Two species of green algae (Caulerpa another crustacean, is often mistaken for and 1990 estimates. The 3-4 year pulse racemosa and Codium sp.), two species lobster by some fishermen. It is harvested of other juveniles (i'e', aguas, and ti'ao) of red algae (Gracilaria edulis and by hooks and gaffs, shrimp traps, and was also observed in 1991 and falsely Asperagopsis sp.) and one species of through incidental catches. elevated the survey estimates (number brown algae (Sargassum polycystum) are Smith (1986) stated that other inverte­ of participants, gear, catch, etc.). If the commonly harvested (Hedlund, 1977). brates harvested have included two spe­ juvenile harvest values were removed The green algae or seaweed is seasonal cies of sea urchins (Tripneustes gratilla from all years, the 1991 harvest esti­ (usually January through May) and when and Echinometra mathaei), two species mate would still be smaller than any collected, is often sold at local markets. of sea cucumbers (Stichopus horrens and previous year. Holothuria atra) and a freshwater shrimp Sargassum and Enteromorpha sp. are also Day Fishing Estimates collected as bait for rod and reel fishing (Macrobrachium sp.). The sea urchin T 4 for herbivores . gratilla has been harvested for ripe go­ Day harvest and effort values for Many molluscan species have been nads. The harvest of sea cucumbers is means for reef fisheries during 1982­ and are still harvested on Guam. About sporadic (H. atra is the most common 91 are shown in Figure 4. A 60% de­ 15 bivalve species (3 of which are species harvested). Present harvest is less cline in the number of fishermen tridacnid clams) have been harvested than that reported in the late 1800's, when occurred in 1990 (30,396) from a high on Guam (Stojkovich and Smith, 1978). catches of 2-3 tons were documented in 1984 (97,603). Similar trends for Other shelled mollusks collected in­ (Amesbury et al., 1986). inshore finfish are seen for both effort clude Trochus sp. (topshell or aliling), Five species of sea turtles have been and catch (Fig. 4) where highs occurred chitons, conchs, nerites, and strombids identified in Guam's waters5. Harvest in 1984. Catch follows effort until 1988 (Smith, 1986). A few of these mol­ of sea turtles on Guam was prominent when harvest continues to drop while lusks (plus some not mentioned) are prior to World War II and occurred the effort increases. Nonfinfish effort collected for ornamental use. The oc­ declined over 90% by 1989 (2,759g­ topus is the most sought after unshelled SHensley, R. A. The distribution and abundance hr) from a high in 1982 (28,613 of marine turtles from 1966 to 1992 in the g-hr). Harvest of nonfinfish, though waters of Guam. Texas Parks and Wildlife De­ 4R. A. Hensley, DAWR, P.O. Box 2950, Agana, partment, 1231 Agnes St., Corpus Christi, TX underestimated, declined from 29,499 Guam 96910. Personal observ. 78401. Unpubl. manuscr. kg in 1982 to 1,289 kg in 1990. Both

55(2), 1993 133 finfish and nonfinfish show declines in finfish in 1987 (58,893 g-hr) and de­ 1989-90 (from >2,000 to 340 g-hr). effort and harvest estimates for 1988-91 clined more than 50% to a low in 1990 The overall night harvest was com­ as compared with the 1982-87 period. (25,181 g-hr). Night harvest of finfish posed of nonfinfish harvest that ranged rose to a high of 23,538 kg in 1988 from 3.2% (361 kg) in 1989 to 23% Night Fishing Estimates before declining to less than 50% in (4,684 kg) in 1986. During the night surveys from 1985 1991 00,285 kg). Nonfinfish showed through 1991, effort reached a high for little change in effort until the drop in

I'" Effort - Catch I

300,000 180,000 :\ 160,000 .. ' 'Ill 250,000 ~ 140,000 0 f .' .. 200.000 120,000 ~ ..Ol '" 100,000 ~ I- a: 150.000 :r 0 U u. 80,000 I­ u. « w U 100,000 60,000

40,000 50,000 20,000

0 0 FY82 FY83 FY84 FY85 FY86 FY8? FY88 FY89 FY90 FY91 SURVEY PERIOD

Figure 3.-Estimated effort and harvest of Guam's nearshore reef fisheries from 1982 through 1991 (catch = harvest of all finfish and nonfinfish for both day and night, FY = 12-month fiscal year),

1- G-HoUf5 , .. Catch I

300,000 140,000

120,000 250,000 Vi' a: => 100,000 0 :r 200,000 ~ 80,000 I-a: , 50,000 0 u. u. 60.000 w 100,000 ...... 40,000

50.000 20,000

+----+--+----+--+----+---+---+---+---+--+ 0 FY82 FY83 FY84 FY85 FY86 FY8? FY88 FY89 FY90 FY91 SURVEY PERIOD

Figure 4,-Estimated effort catch of Guam's inshore fisheries for the daytime from 1982 through 1991 (catch = total harvest of finfish without maiiahak or atulai harvest, FY = 12-month fiscal year),

134 Marine Fisheries Review Gear Usage and CPUE slightly lower CPUE's for spearfishing program at the University ofGuam where with scuba and "other". Night CPUE's students investigate important species like The most popular fishing methods fluctuate more than day CPUE's and Acanthurus triostegus, A. lineatus, and for day and night are seen in Figures 5 are highest for spearfishing, drag net­ Naso literatus (Molina, 1983; Davis, and 6, respectively. Hook and line is ting, and gill netting. Much of the 1985). Even with the research being done the most popular method for both day CPUE fluctuations, especially with net by local and visiting scientists, there is and night, but consistently has one of fishing methods like cast, drag, and still an enormous amount of information the lowest CPUE's (catch per unit of gill net, can be attributed to the sea­ lacking on Guam's fishes. effort) ranging from 0.05 to 0.36 for sonal aspect of the fisheries with re­ both day and night. The second and Work toward identifying the many spect to traditional fish harvests. third most popular methods for day fish species in Guam's waters has oc­ curred (Kami et ai., 1968; Kami, 1971, fishing are cast and gill net. During Research 1982-84, "other" displaced gill net 1975; Myers and Shepard, 1980; from the top three. After 1985, most of The DAWR has been involved in Shepard and Myers, 1981; Amesbury the participation can be seen with the many aspects of research. For many and Myers, 1982; Myers, 1988, 1989). top three methods (hook and line, cast years, aquaculture potential for fresh­ This documentation continues as new net, and gill net). water finfish was investigated. Cur­ species are recorded. The species com­ Figure 6 shows the most popular rently, aquaculture research is still position of the fishery on Guam has night fishing methods. Spearfishing conducted (marine finfish and inverte­ been made possible by the various with snorkel gear ranks second, more brates) and involves another govern­ check-lists of the fishes in Guam's often than gill net, drag net, or ment agency, private companies, and waters. Aerial surveys are periodically "other"methods. Except in 1985, when the University of Guam. Most recently, performed to monitor inshore fishing "other" displaces gill net from its third DAWR began a study of the feasibility activity in nonsurveyed areas of Guam. ranking, gill net fishing has increased of restocking the giant clam Tridacna Incidental information acquired in­ in popularity where it ranked second derasa. Studies on the biology and life cludes offshore fishing information and 5 for 1986-91. histories of some recreationally impor­ turtle abundances . Many gear use fluctuations are due tant fishes began in 1984. To date, Future investigations are planned for to the popularity of methods with high Siganus spinus and Mulloides flavo­ other recreationally important reef spe­ CPUE's. The highest day CPUE's (usu­ lineatus biological profiles have been cies to make sound management sug­ ally about 2.0-4.7) are most often seen completed, with Lethrinus harak in gestions (size, bag limits, seasonal with net fishing (mainly drag net, sur­ progress. These biological investiga­ closures). Otolith work has been initi­ round net, and gill net) followed by tions have been aided by the graduate ated through the University of Guam.

• Hook and Une IillII Cast Net • Gill Net o Surround Net • SPEAR SNORKEL IIIi OTHER

70,000

60,000 .,c E., SO,OOO .z= u:Ul ... 40,000 0 .,~ .Q 30,000 E ~ Z 20,000

10,000

0 "~ "~ "M "~ "~ "~ "~ "~ "~ "~ SURVEY PERIOD

Figure 5.-The most popular fishing methods in Guam's inshore fisheries for the day from 1982 through 199\ (number of fishermen = number of people using specific method; FY = 12-month fiscal year.)

55(2),1993 135 • Hook and Line [iill\ Gill Net • SPEAR SNORKEL 0 DRAG NET • OTHER

14,000

12,000 c:

E'" 10,000 ~ .s::. u::III 8,000 '0

~ .0 6,000 '"E :J Z 4,000

2,000

0 FY 8S FY 86 FY 87 FY 88 FY 89 FY 90 FY 91 SURVEY PERIOD

Figure 6.-The most popular fishing methods in Guam's inshore fisheries for the night from 1985 through 1991 (number of fishermen = number of people using specific method, FY = 12­ month year).

Analyses of the stocks and future fish­ Both types of fishing are illegal, but chus, and crabs. Gear restrictions are ing potential is continuing through the through an education program (with the only regulations pertaining to fin­ modifications in existing expansion respect to problems associated with fish harvest. Minimum mesh sizes of methodology and creel survey infor­ destructive fishing practices) and strict 1 1/2 inches on gill nets (except for tra­ 6 mation . enforcement, these have been declining. ditional or juvenile harvest) and hook Besides pollution and destruction of restrictions for atulai (no snagging) are Management Concerns the reef habitat, it is imperative that a the principal restrictions. Other gear As the human population grows, comprehensive management program restrictions include length and time lim­ modern fishing techniques improve, be established for Guam's fisheries. its for gill net fishing and the prohib­ and fish stocks decline, the need for There are enough indicators that fish­ ited use of fish weirs. the management of Guam's tropical ing pressure on Guam's inshore re­ New regulations are currently await­ coral-reef fisheries increases in order sources has reached the point of ing approval with one of the most to protect the reef habitat from over­ overexploitation of many of the key promising avenues being the develop­ fishing as well as from pollution and species. The proportion ofjuvenile fish ment of marine conservation area(s). destruction, The effects of pollution in fisheries landings is increasing rap­ These should be established to provide are seen as a result of development and idly. "Growth overharvesting" has been a refuge for recreationally important population growth. Much of Guam's occurring, and the overall yield has fish so they can grow, mature, and re­ southwestern coral reefs are covered declined as a larger and larger portion produce to increase stock health and with silt from freshwater runoff. Be­ of smaller fish are harvested. It is very recruitment. Besides the ability of an cause water quality is extremely im­ likely that "recruitment overharvest­ area closure to protect fish from har­ portant to viable coral reefs (and fish ing," where the reproduction and re­ vest, there are many other benefits that populations), strict standards for de­ cruitment of the stocks show a decline, make this an increasingly popular form velopment, land clearing, and chemi­ is currently occuring in some of the of management and conservation. The cal use should be initiated and enforced. recreationally important species. closure limits the catches on adjacent Other major causes of reef destruction reefs without closing down the entire Management Recommendations includes the use of explosives and poi­ fishery and provides areas where user soning (chlorine bleach and Bar­ Currently, there are several seasonal, conflicts are minimized. ringtonia root) as fishing methods. area, gear, and size restrictions and bag Gear restrictions should be imple­ limits on Guamanian fisheries. These mented and enforced. Because no other 6Hensley, R. A., and T. S. Sherwood. Unpubl. data. Texas Parks and Wildlife Department, pertain mostly to nonfinfish such as method for the seasonal harvest (with 1231 Agnes St., Corpus Christi, TX 7840 I. the spiny lobsters, tridacnid clams, Tro­ mesh sizes as small as 1/4 inch) is as

136 Marine Fisheries Review dangerous to the entire fishery as the for whole reef fish, the financial ben­ coral harvesting, gill net abandonment, nonselective method of gillnet fishing, efit for fishermen using a high CPUE etc.). The DAWR continues to address this method should be heavily regu­ method (gill net, surround net, drag the aspect of educating tourists (over lated. The minimum mesh size for gill net) is enormous. Many of the net fish­ 740,000 in 1990) and temporary work­ nets should be 3 inches, maximum ermen encountered on the inshore sur­ ers from foreign lands about local regu­ length of time used should be de­ vey are no longer subsistence fishermen lations. As Guam's population and a creased, and it should be required that but are commercial fishermen. need for housing increases, illustrated all nets be manned at all times. The use Reef fish imports from Belau and by the recent closure of the U.S. mili­ of gill nets for juvenile fish harvest the Federated States of Micronesia are tary bases in the Philippines and the should be eliminated (except atulai increasing. It is difficult to determine subsequent transfer of 2,000 families where a Ilh-inch minimum mesh size the amount of fish imported because to Guam, we see greater threats to the should be kept). Other nets, like cast few restrictions are placed on importa­ reef resources than we have now. With nets and drag nets could still be used tion. Further difficulties occur in moni­ the help of the general population and for juvenile harvest without the dam­ toring sales of local and imported fish the passage of rigid regulations, there age to the fish stocks that gill netting because of the manner in which they is still hope for the fishery to rebound. may cause. All commercial fishing for are sold. Many fishermen sell their However, it is highly unlikely for fu­ seasonal juveniles using nets with mesh catch on the roadside, while others sell ture harvests to reach pre-1987 totals. sizes less than l'h inches should be to small local stores or the large super­ Acknowledgments prohibited. Because of the environmen­ markets. Continued monitoring is nec­ tal damage that sometimes occurs with essary to obtain more knowledge of We would like to thank M. 1. drag nets, the use of this method should the commercial aspect of the inshore McCoid and G. W. Davis for their criti­ be restricted to specific areas where fisheries. cal review of this manuscript and all minimal destruction of habitat would the data collectors that were involved The Future occur. Spearfishing with scuba gear in this project over the years. We also should be prohibited because the few The outlook for Guam's inshore fish­ thank G. Boehlert and two anonymous remaining large fish of overexploited eries, given the current catch informa­ reviewers for their comments. This species are being targeted. tion, is poor. If management strategies project was funded by the Federal Aid in Appropriate management strategies are not incorporated soon, the remain­ Sport Fish Restoration Act (Guam Fish­ are difficult to develop when dealing ing fishery may continue to decline to eries Investigation-Project FW-2R-22). with multispecies, multigear fisheries. the point of poor productivity. The need Management is further impeded by the for fishery imports will continue to in­ Literature Cited desire to hold on to traditional fishing crease as local stocks decline. This Amesbury. S. S., and R. F. Myers. 1982. Guide activities which involve the harvest of lower abundance and availability of to the coastal resources of Guam, Volume I: juvenile fishes. To ensure that future Guam's fishery resources could cause The fishes. Univ. of Guam Press, Mangilao. 141 p. generations enjoy the traditional har­ higher fishing pressure on neighboring _~-,-' F. A. Cushing. and R. K. Sakamoto. vest ofjuveniles as well as other fishes, islands. 1986. Guide to the coastal resources of strict management regulations must be The ability to manage Guam's fish­ Guam. Volume 3: Fishing on Guam. Univ. of Guam Press, Mangilao. 110 p. implemented. Of course, the ability of eries is limited by local politics. In an _~-,----,,' T. S. Sherwood, and G. W. Davis. any management approach also de­ effort to protect the traditional fishing 1991. Monitoring a tropical island reef fish­ ery. Am. Fish. Soc. Symp. 12: 84-87. pends on ensuring a healthy and clean practices of the Chamorus, legislation Davis, G. W. 1985. Reproductive patterns of reef environment to provide adequate has been passed without any apparent three economically important surgeonfish habitat and optimal reproduction. foresight of impact on other aspects of species on Guam. M.S. thesis. Univ. of Guam, Mangilau, 44 p. the fishery. Interpretation of the term Market Description Hedlund. S. E. 1977. The extent of coral, shell "traditional" has allowed fishing prac­ and algal harvesting in Guam waters. Univ. The DAWR has been keeping track tices acquired since WWII (i.e., gill of Guam, Tech. Rep. No. 37, 34 p. Ikehara. 1. 1.. H. T. Kami and R. K. Sakamoto. of the catch sold by offshore recre­ netting) to continue with little to no 1970. Exploratory fishing survey of the in­ ational fishermen (Myers, 1993) and regulation. If allowed to continue, the shore fisheries of Guam. Proc. 2nd CSK Symp.• Tokyo: 425-437. has recently begun to document other change from subsistence fishing to "tra­ Johannes. R. E. 1978. Traditional marine con­ catches, including nearshore reef fishes. ditional" commercial fishing will con­ servation methods in Oceania and their de­ The market for nearshore reef fish has tinue to strain Guam's fishery resources. mise. Annu. Rev. Eco!. Syst. 9:349-364. Kami, H. T. 1971. Check-list of Guam's fishes. increased on Guam, especially with the The picture is not as bleak as it may Supp!. 1. Micronesica 7(1-2):215-228. diverse cultures that eat fish as a pri­ appear, however, because many Gua­ --c;::-----:-' 1975. Checklist of Guam's fishes, mary source of protein. With the in­ manians are beginning to become en­ Supp\. II. Micronesica I I(2): I 15-121. __-.,-and 1. 1. Ikehara. 1976. Notes on the flux of new people and the desire for vironmentally aware. This is annual juvenile siganid harvest in Guam. local fresh fish, the market continues demonstrated by the increasingly high Micronesica 12(2):323-325. _~-,-' •and F. P. DeLeon. 1968. to expand. Because the prices are high, number of informants regarding ille­ Check-list of Guam's fishes. Micronesica with the average price of $3-4/pound gal fishing practices (turtle poaching, 4(1):95-131.

55(2).1993 137 Katnik, S. E. 1982. Effects of fishing pressure Myers, R. F. 1988. An annotated checklist of Mariana islands. In A working list of marine on the reef flat fisheries of Guam. M.S. the­ the fishes of the Mariana Islands. organisms from Guam, p. 60-88. Univ. of sis, Univ. of Guam, Mangilao, 62 p. Micronesica 21 (1-2): 115-180. Guam Tech. Rep. No. 70. Kerr, A. M. 1990. Chamorro fish names. _-=-----:-..,. 1989. Micronesian reef fishes. Coral Smith, B. D. 1986. Reef invertebrate harvest­ Micronesica 23(2): 93-118. Graphics, Barrigada, Guam, 298 p. ing. In Guide to the coastal resources of Malvestuto, S. P., W. D. Davies, and W. L. Shelton. _----:_~. 1993. Guam's small-boat-based fish­ Guam,Volume 3: Fishing on Guam, p. 68­ 1978. An evaluation of the roving creel survey eries. Mar. Fish. Rev. 55(2):117-128. 74. Univ. Guam Press, Mangilao. with nonuniform probability sampling. Trans. _----::--:::-,...and J. W. Shepard. 1980. New records Stojkovich, J. 0., and B. D. Smith. 1978. Sur­ Am. Fish. Soc. 107(2):255-262. of fishes from Guam, with notes of the ich­ vey of edible marine shellfish and sea ur­ Molina, M. 1983. The seasonal and annual varia­ thyofauna of the southern Marianas. chins on the reefs of Guam. Univ. Guam, tion of coral-reef fishes on the upper reef Micronesica 16(2):304-347. Tech. Rep. No.2, 65 p. slope at Guam. M.S. thesis, Univ. of Guam, Shepard, J. W., and R. F. Myers. 1981. A pre­ Mangilao, 87 p. liminary checklist of Guam and the southern

138 Marine Fisheries Review