Abesamis et a\ : How much does the fishery at Apo Island benefit from spillover from a marine reserve' 



371 



spp.) (Alcala and Luchavez. 1981; White and Savina, 

 1987; Bellwood, 1988; Maypa et al., 2002; present 

 study). Ninety-two percent of total hook-and-line effort 

 was made on the northern fishing grounds of the island. 

 Gill nets, spear guns, and fish traps were not used as 

 much as hook-and-line; however, fishing with these gear 

 was also carried out mostly on the northern fishing 

 grounds, contributing to a yield of reef-associated spe- 

 cies and reef planktivores. Fishing near Apo Reserve 

 contributed mainly to catch of reef species (Scaridae 

 and octopus), which are a less important species group 

 for the local fishery. The fishery depended heavily on 

 access to the northern fishing grounds during the SW 

 monsoon and calm interim period (Bellwood, 1988; pres- 

 ent study). Results clearly showed that fishing effort on 

 the northern fishing grounds was considerably lower 

 during the NE monsoon, especially for hook-and-line 

 gear and gill nets. However, fishing effort did not shift 

 to the fishing grounds near Apo Reserve during the 

 NE monsoon. Gillnet fishing seemed to transfer instead 

 to the western fishing grounds, targeting reef species 

 (Scaridae). To a much lesser degree, hook-and-line fish- 

 ing also transferred to the western fishing grounds, 

 targeting high-value off-reef species (Aphareus furca 

 [Lutjanidae]). The northern fishing grounds alone ac- 

 counted for 78% of overall yield and 81% of overall 

 income recorded in our study (Table 1). In contrast, 

 fishing grounds near Apo Reserve accounted for only 

 10% of overall yield and 9% of overall income (Table 1). 

 However, it is highly unlikely that spillover from Apo 

 Reserve supplied the entire yield taken from fishing 

 grounds near the reserve. That is, the yield near the 

 reserve was probably not composed totally of migrants 

 from the reserve. Therefore, the actual spillover contri- 

 bution of Apo Reserve would be much less than 10% to 

 the overall yield and income generated by the fishery. 



However, CPUE of fishermen was highest on the fish- 

 ing grounds near Apo Reserve. This pattern may have 

 resulted from 1) spillover from the reserve or 2) lower 

 fishing intensity near the reserve, resulting in higher 

 abundance of fish and, thus, higher CPUE. There is 

 far more empirical evidence supporting the spillover 

 hypothesis than the lower fishing intensity hypothesis. 

 Considerable evidence exists that some supplement for 

 the fishery near the reserve has developed over time. 

 Firstly, monitoring of Apo Reserve since 1983 has 

 shown that fish populations inside the reserve have 

 increased in abundance, some having tripled in density 

 or biomass over the last two decades (Russ and Alcala, 

 1996, 1998, 2003; Russ et al., 2003, 2004; Alcala et al., 

 2005). Secondly, long-term monitoring indicates that 

 the reserve began to export adult fish to a site open to 

 fishing after ~8 years of reserve protection (Russ and 

 Alcala, 1996; Russ et al., 2003, 2004). Thirdly, catch 

 rates of some species (Acanthuridae) were found to be 

 higher near the reserve than elsewhere around Apo 

 Island after two decades of reserve protection (Russ et 

 al., 2003, 2004). Fourthly, recent studies indicate that 

 patterns of decreasing abundance of some targeted spe- 

 cies are present across the northern boundary of the 



reserve (Abesamis et al., 2005). Lastly, a recent study 

 indicates that density-dependence may be driving net 

 emigration of adult fish (Naso vlamingii (Valenciennes)) 

 from the reserve (Abesamis and Russ, 2005). On the 

 other hand, no direct evidence is available to show that 

 fishing effort near Apo Reserve has remained low over 

 the last two decades. However, the fishing grounds near 

 the reserve may be partially exposed to the SW and NE 

 monsoons (Alcala and Luchavez, 1981). During the SW 

 monsoon, the fishing grounds adjacent to the southern 

 end of the reserve may become rough, but those ad- 

 jacent to the northern end are usually calm (Fig. 1). 

 The pattern is reversed during the NE monsoon. Thus, 

 fishing effort near the reserve may be reduced for nine 

 months of the year (June to September, November to 

 March) because only the area close to one side of the 

 reserve may be fished, depending on the monsoon. The 

 role of the monsoons in limiting fishing effort near the 

 reserve cannot be ruled out entirely. 



If spillover has increased CPUE near the reserve, as 

 long-term evidence seems to indicate, then why have 

 local fishermen not responded noticeably to the im- 

 provement in catch rates? Weather may be important 

 in limiting fishing effort near the reserve, but it cannot 

 explain the low fishing intensity in this area during 

 the calm interim months. Results show that hook-and- 

 line and gillnet effort on the fishing grounds near the 

 reserve in October were still considerably lower than 

 on the northern fishing grounds (Fig. 2, A and B). An- 

 ecdotal information also indicates that most fishermen 

 still prefer to fish the northern fishing grounds even 

 during April and May (Pascobello-). This information is 

 consistent with the findings of previous studies (White 

 and Savina, 1987; Bellwood, 1988; Maypa et al., 2002), 

 which indicate that the general pattern of fishing effort 

 at Apo Island has not changed much since creation of 

 the reserve in 1982. Furthermore, a reasonable amount 

 of fishing area (8-11 ha) near the reserve is still avail- 

 able to fishermen during either monsoon. Given the 

 higher catch rates, fishermen could still concentrate 

 effort near the reserve, one side of the reserve at a 

 time, depending on the monsoon. Higher costs (time 

 and energy spent to paddle a small boat [banca]] are 

 certainly not preventing fishermen from fishing adjacent 

 to the reserve. The majority of fishermen (80%) reside 

 near the reserve, in Baybay and Ubos villages (Fig. 1) 

 and therefore for most fishermen the costs of fishing the 

 northern side of Apo Island may actually be higher. It 

 is also unlikely that fishermen are not aware of higher 

 catch rates near the reserve. Fishermen can probably 

 obtain good information about catch rates from the 

 experiences of fellow fishermen, or from word-of-mouth, 

 because the community is relatively small and tightly 

 knit. Many fishermen are members of the same family 

 (including cousins and uncles) or are friends with each 

 other. Income rates per se can also be ruled out as an 



- Pascobello, M. 2002. Personal commun. Apo Island resi- 

 dent and village chairman. Apo Island, Dauin Municipality, 

 Negros Oriental, Philippines, 6217. 



