Predator-prey interactions have a major effect on species abundance and diversity, and aggregation is a well-known anti-predator behaviour. For immobile prey, the effectiveness of aggregation depends on two conditions: (a) the inability of the predator to consume all prey in a group and (b) detection of a single large group not being proportionally easier than that of several small groups. How ...

Lake Sonachi, Kenya, is a small alkaline-saline crater lake that over the past 175 years has experienced considerable fluctuations in lake depth (Zmax 5 3–18 m) and an alternation of meromictic and holomictic episodes lasting from a few years to several decades. Paleolimnological methods were used to reconstruct the long-term dynamics of algal and invertebrate communities in Lake Sonachi in rel...

Polytene chromosomes of chironomid larvae (Diptera: Chironomidae), collected on the Wrangel Island are described. Larvae have 2n=8: AB, CD, EF, G (Ch. thummi Keyl, 1962 complex). By karyotype larvae are identical to Chironomus sp. Le1, described from the Sagystyr Island of the Ust-Lena Reserve (Yakutia) (Kiknadze et al., 1996). The insignificant differences include the number of nucleoli and pu...

Soft bottom macrobenthic communities were studied seasonally in three coastal ponds (Marinello ponds, Italy) at increasing distances from a gull (Larus michahellis) colony to investigate the effect of seabird-induced eutrophication (i.e. guanotrophication) on macrobenthic fauna. We hypothesized that enhanced nutrient concentration and organic load caused by guano input significantly alter the t...

Methods and growth chambers are described which permit in situ estimates of the growth rates of chironomid larvae inhabiting litter accumulations in lotic habitats. Instantaneous growth rates (IGRs) for larvae of different sizes ranged from 0.01 to 0.24 mg mg-l ash-free dry mass (AFDM) d-l at stream temperatures of 2.9”15.1”C. IGRs were significantly and linearly related to temperature. Regress...

Oukuriella Epler, 1986 is an exclusively Neotropical genus that comprises two well supported clades: inhabitants of freshwater sponges and inhabitants of immersed wood (saproxylophilic). In this work, males of a new chironomid species, Oukuriella froehlichi sp. n., are described and illustrated. Specimens were collected near stream in the Brazilian Atlantic Forest. Phylogenetic analyses perform...

—Stream fishes can have strong top-down and bottom-up effects on ecosystem processes. However, the dynamic nature of streams constrains our ability to generalize these effects across systems with different disturbance regimes and species composition. To evaluate the role of fishes following disturbance, we used a series of field and mesocosm experiments that quantified the influence of grazers ...

Bottom-living oligochaetes and chironomid larvae, thanks to their supposedly integrative power, could provide more robust measures of the water quality lakes than separate chemical data. The oligochaete fauna large southern Scandinavia has been studied in detail over many years—often 100 years or (Milbrink, 2020). Characteristic species associations ecological preferences each are thus relative...