Aeneolamia Fennah, 1949 (Hemiptera: Cercopidae) attacks pastures in Roraima, with first report in Brazil

Spittlebugs (Hemiptera: Cercopidae) are the predominant pasture pests in Brazil, mainly the Amazonia region. Despite frequent reports of attacks by these spittlebugs in Roraima, information on this insect group is scarce. Therefore, we conducted surveys and a population dynamic study in pastures in Roraima from May 2015 to July 2019. We identified the spittlebugs Aeneolamia flavilatera (Urich, 1914) and Aeneolamia reducta montana (Lallemand, 1944). This is the first report of A. reducta montana in Brazil, and the first report of A. flavilatera attacking pastures. We discuss the possible impacts of these pests on Brazilian agriculture and livestock.

On selection-regulated population dynamics in birds and mammals

I use the North American Breeding Bird Survey (Sauer et al. 2017) to construct 462 population trajectories with about 50 yearly abundance estimates each. Applying AIC model-selection, I find that selection-regulated population dynamics is 25,000 (95%:0.42-1.7e17) times more probable than density-regulated growth. Selection is essential in 94% of the best models explaining 82% of the population dynamics variance across the North American continent. Similar results are obtained for 111, 215, and 420 populations of British birds (BTO 2020), Danish birds (DOF 2020), and birds and mammals in the Global Population Dynamic Database (GPDD 2010). The traditional paradigm---that the population dynamic growth rate is a function of the environment, with maximal per-capita growth at low population densities, and sub-optimal reproduction from famine at carrying capacities with strong competition for limited resources---is not supported. Selection regulation generates a new paradigm where the world is green and individuals are selected to survive and reproduce at optimal levels at population dynamic equilibria with sufficient resources. It is only the acceleration of the population dynamic growth rate, and not the growth rate itself, that is determined by the density-dependent environment, with maximal growth occurring at the densities of the population dynamic equilibrium.

Population dynamic of skipjack (Katsuwonus pelamis) in Timor Sea, East Nusa Tenggara, Indonesia

Skipjack tuna is one of the potential fishery commodities in the waters of Timor, East Nusa Tenggara. This fish is exploited throughout the year without any management policies. This study aims to analyse population dynamic parameter. Length data were collected at the Oeba Fish Base from April to December 2020. Data analysis, size structure and age group of the Bhattacharya method, the L∞ and K values of the Ford and Walford method, total mortality by length catch converted curve, natural mortality by Pauly method, Y/R using the Beverton and Holt method. The results showed that the smallest fish was 27 cm FL, the largest was 71 cm FL, the dominant size is 55-58 cm FL and the average length was 48,68 ± 10,67 cm FL, L∞ 91.00 cm FL, and K 0.51 year1. The population consists of three age groups, the values of Z, M, F and E are 2.64 year1, 0.86 year1, 1.78 year1, and 0.68 year1 respectively. Current Y/R and optimal Y/R values are 0.036 and 0.060 grams recruit1 respectively. The conclusion, the high mortality of skipjack tuna is caused by fishing activities, and the high level of exploitation causes the recruitment process to be not optimal.