Carry-over effects of the larval environment on the post-metamorphic performance of Bombina variegata (Amphibia, Anura)

Metamorphs of the yellow-bellied toad, Bombina variegata, vary widely in size at metamorphosis in the field. We performed a replicated outdoor mesocosm study to simulate the environmental factor combinations in permanent and ephemeral breeding sites and to quantify their effects on tadpole development (duration of the larval period, metamorph size and body condition). Looking for potential carry-over effects of the larval environment, we quantified locomotor performance of all metamorph phenotypes originating from the mesocosms immediately after metamorphosis under controlled conditions. In contrast to the prediction of life-history theory, tadpoles were unable to adjust developmental rate to water availability, but metamorphs originating from the ephemeral pond treatment were smaller and had a lower body condition than those from the permanent pond treatment. Size-dependent carry-over effects included the length of the first jump following tactile stimulation, burst performance (total length of spontaneous jumps) and endurance (total distance covered in 10 forced jumps). A size-independent effect of larval environment was the prolonged locomotor effort to escape (5.7 consecutive jumps following initial stimulus) of metamorphs from the ephemeral pond treatment compared to same-sized ones (3.7 jumps) from the permanent pond treatment. Thus, we demonstrate that carry-over effects of larval environment on metamorph phenotype and behaviour cause a considerable variation in fitness in the early terrestrial stage of B. variegata. Informed conservation management of endangered populations in the northern range should therefore include the provision of small permanent breeding ponds promoting larger and fitter metamorphs.

ANALISIS KELAYAKAN FINANSIAL USAHA BUDI DAYA IKAN LELE DUMBO (Clarias gariepinus) DI KOLAM TERPAL DAN KOLAM PERMANEN PADA UD. REPUBLIK LELE KABUPATEN KEDIRI

The purpose of the study was to analyze the financial feasibility of Clarias gareipinus cultivation in tarpaulin ponds and permanent ponds UD. Republik Lele in Kediri Regency, East Java. The method used is the analysis of profit-loss calculations using the Net Present Value (NPV), Internal Rate of Return (IRR), Net B / C Ratio, Pay Back Period (PBP), and Break Event Point (BEP). The results of the study show that. The results showed that the stages of catfish cultivation included the process of spawning, catfish egg hatching, seed grading, and the augmentation process. Spread density in permanent ponds of 500 seedlings / m2, tarpaulin ponds of 450 seedlings / m2 as a whole the business of profitable catfish cultivation, with an average net pool profit of Rp. 23,918,347 / cycle / pond and tarpaulin pool Rp. 19,005,054 / pool / cycle. Based on the analysis of financial feasibility of permanent ponds and tarpaulins in a row generate (NPV) Rp. Rp 5,975,446,295 and Rp 1,645,894,923 (IRR) of 17.62% and 10.57%, (PBP) for 3 years and 3 years 9 months, Net B / C Ratio of 1.20 and 1.19, and (BEP) in the amount of Rp. 11,082,314,678 and Rp. 8,238,792,702/year. This business is feasible to be developed. Keywords: financial feasibility, tarpaulin pool, permanent pond, catfish

Seasonal maturation of Glypthelmins vitellinophilum (Trematoda: Digenea) in Lysapsus limellus (Anura: Pseudidae) from an Argentinian subtropical permanent pond

From December 1995 to November 2000, the seasonal maturation of Glypthelmins vitellinophilum Dobbin, 1958, in its definitive host, the frog Lysapsus limellus Cope, 1862, was studied in a subtropical permanent pond in northeastern Argentina. The objectives of this study were: 1) to determine the infrapopulation dynamics of the parasite, analyzing the seasonal maturation cycle throughout the years; and 2) to examine the relationship between the intensity of trematode infection in different developmental stages (recruitment, growth and maturation) and the host's body length. Of a total of 1,400 frogs examined over 60 months (5 years), 38% were found to be infected with G. vitellinophilum, and the intensity of infection was 1-15 trematodes per frog. Specimens of G. vitellinophilum were present in L. limellus throughout the years, but did not show a pronounced seasonal maturation cycle. Possible reasons for these findings are discussed with reference to climatic fluctuations and biotic factors. The infective period of the parasite (stage I) occurred in summer, autumn and spring, coinciding with the time each frog cohort appeared. These infections were found principally in small body sizes (classes 1 and 2) of L. limellus. Juvenile and nongravid specimens of worms (stage II and III) were found in frogs of different body sizes throughout the period of investigation. Gravid specimens of the parasite (stage IV) were generally recorded in autumn, winter and spring, mainly in the bodies of larger frogs. The body length of Trematodes in stages I and IV was significantly and positively correlated with that of the frogs.

COMPARATIVE ECOLOGY OF TWO SPECIES OF HYDROPORUS (COLEOPTERA: DYTISCIDAE) IN A HIGH ARCTIC OASIS

At Alexandra Fiord, Ellesmere Island, the diving beetles Hydroporus morio Aubé and Hydroporus polaris Fall occur in a series of shallow ponds. Detailed habitat measurements of a temporary and a permanent pond revealed a more complex and extensive organic substrate and vegetation community, longer developmental time, and greater thermal budget in the permanent pond. Hydroporus polaris was most abundant in the temporary pond, but occurred in both; this species oviposited in the absence of macrophytic vegetation, completed larval development quickly, and pupated in the drying pond substrate, and adults dispersed in fall to moister overwintering sites. Hydroporus morio was restricted to the single permanent pond; this species took longer to complete larval development, pupated in wet moss, and overwintered as adults encased in ice on the vertical pond edge. We hypothesize that H. morio is excluded from temporary ponds in the arctic by its requirement for a relatively long development time. Alternatively, H. morio may require sheltered overwintering sites that temporary ponds do not offer.