No abstract

Studies on butterflies in the Philippines are scanty and some areas still need to be explored, especially in Butuan City, Agusan del Norte. The current study provided information on the species composition and status of true butterflies in Lauan Eco Park and Bood Promontory Eco Park, Butuan City. The studies employed transect walks and opportunistic sampling using insect net-sweeping techniques. A total of 218 individuals of true butterflies belonging to 37 species, 24 genera and four families were documented. 34 species belonging to 22 genera were observed in Lauan Eco Park, while 12 species belonging to 10 genera were recorded in Bood Promontory Eco Park. Of these, the family Nymphalidae was the most represented group having 20 species (54.05%) in two sites, followed by the family Pieridae with 11 species (29.72%); the family Lycaenidae with four species (10.81%); and the family Papilionidae as the least represented group with only two species (5.40%). Regarding national status and endemism, 25 (71%) out of 35 species were common, 1 (2.70%) rare species, 1 (2.85%) rare Mindanao endemic and 8 (22.85%) were Philippine endemic species; five (5) species were rare Philippine endemics and four (4) species were common Philippine endemics.As for the local status, 25 species were assessed as very rare, seven (7) were rare, three (3) were common and two (2) were very common. New locality record of Ptychandra lorquinii plateni and Mycalesis igoleta were reported in Agusan del Norte. Lauan Eco Park showed a higher number of individuals (156) than Bood Promontory Eco Park (65). Diversity assessment using the Shannon-Weiner index showed a high index with H = 2.92 in Lauan Eco Park compared to Bood Promontory Eco Park with H = 1.933. The species richness, abundance and diversity of butterfly species, plus the presence of rare endemic species in Eco Parks, are essential for conservation and protection as a habitat for butterfly species.

Channa striata Bloch is a type of indigenous freshwater fish abundant in Lake Mainit and it serves as a source of foods and finances of the people. This species was reported as an intermediate host of many helminth parasites. This research aimed to determine the association of endo-parasites, diet composition, and length and weight in snakehead fish C. striata Bloch in three selected municipalities along Lake Mainit, Caraga Region, Philippines. The results revealed that food items found in the stomach of the fish were mostly composed of shrimps, plant debris, fish, crab, detritus (dry & wet seasons), aquatic insects and snail (wet season). Among the seven food items, highest index of relative importance (IRI) value observed are shrimps in both wet and dry seasons. A nematode parasite was recovered in the gut of the fish samples. Out of 180 fish samples, 133 were infected with Procamallanus sp. The prevalence was higher in the dry season compared to the wet season. However, parasite intensity and diet count of C. striata Bloch. showed no significant variations between sampling sites and seasons.  On the other hand, there were no significant differences between the intensity of the parasite count to the length and weight of the fish; the association between parasite count and diet count during dry and wet seasons showed a strong positive correlation. The results indicated that C. striata Bloch is susceptible to Procamallanus sp. nematode infection because of its carnivorous diet and serves as the vector or intermediate host in freshwater. Thus, more fish samples, the host’s age, host’s sex, the study gap, infection rate of the fish organs, and assessment of the physico-chemical parameters in future studies must be used.

Lake Mainit is one of the key biodiversity areas in the country, its watershed area is a habitat of endemic and native plant species but is now threatened due to anthropogenic activities such as mining, kaingin and expansion of agriculture. This study assessed the diversity and community structure of plants in the lowland and upland of the two selected areas (Cantugas and Jabonga) of Lake Mainit watershed through a transect and quadrat method. A total of 321 floral species were identified distributed into 85 families. The taxonomically well distributed families were Arecaceae, Moraceae and Fabaceae with 18, 17 and 14 species respectively and most species were trees and shrubs (187 species). The highest species diversity, richness and abundance was observed in the lowland of Jabonga while the highest dominance was observed in the upland of Catugas. The floral species of Lake Mainit watershed are threatened by anthropogenic activities especially expansion of agriculture and tree felling for infrastructure developments regardless of their environmental roles and inherent benefits. Therefore, sustainable conservation efforts should be geared towards ensuring their continuous existence in order to maintain environmental integrity.

Understanding the stoichiometry of nitrogen (N) and phosphorus (P) plays a pivotal role in the ecological restoration of degraded landscapes. Here, the N and P limitation and stoichiometry of dominant tree species in mine-disturbed ultramafic areas in the Southern Philippines are reported. Field surveys revealed that out of a total of 1491 trees/shrubs recorded from all quadrats, comprising 22 native and 9 non-native species, there were six tree species (native: Alstonia macrophylla Wallich., Buchanania arborescens Blume., Syzygium sp., and non-native: Casuarina equisetifolia L., Terminalia catappa L. and Acacia mangium Wild.) that were found dominant, having >10% relative abundance. Significant differences (p < 0.01) in the leaf N and leaf P content among these species were observed, where C.equisetifolia (due to N fixation ability) and T. catappa had the highest values, respectively. These did not, however, translate to statistical differences in the leaf N:P ratios either in individual species or when grouped by origin (native or non-native). Interestingly, all dominant tree species revealed very low leaf N:P ratios (<4), suggesting that N rather than P limits the productivity in mine-disturbed ultramafic areas, which is also confirmed by low levels of leaf N (<2.0%). Results further revealed a poor correlation between leaf N and leaf N:P ratios (r = 0.13; p = 0.60), while leaf P (r = 0.49; p < 0.05) revealed otherwise, reinforcing that P is not a limiting factor as also shown in high levels of leaf P (>0.20%). Despite the N-limitation, B. arborescens, C. equisetifolia, and T. catappa had the highest leaf N and P content, suggesting their higher suitability for revegetation of the sites. These findings warrant further verification taking into account the plant physiology, phenology, and soil nutrient availability in natural, degraded, and rehabilitated ultramafic environments.