Proceedings of the Linnean Society of New South Wales.

v.37=no.145-[148] (1912)

Proceedings of the Linnean Society of New South Wales.

v.35=no.137-140 (1910)

Proceedings of the Linnean Society of New South Wales.

[v.12]=[no.45-48] (1887-1888)

Proceedings of the Linnean Society of New South Wales.

v.23=no.89-92 (1898)

The diet of the South American sea lion (Otaria flavescens) at Río Negro, Patagonia, Argentina, during the winter-spring period

The South American sea lion, Otaria flavescens (Shaw, 1800) population is steadily expanding along the Patagonian coast of Argentina in the last decades. However, little is known about the feeding ecology of the species in the area. The aim of this study was to analyze the food habits of O. flavescens from 91 scats collected at Río Negro province, during the winter and spring of 2005. Fish occurred in 96% of scats containing prey remains, followed by cephalopods (26%). Raneya brasiliensis (Kaup, 1856) was the most frequent and abundant species occurring in 58.6% of samples and constituting almost 50% of fish predated. Second in importance were Porichthys porosissimus (Cuvier, 1829) and Cynoscion guatucupa (Cuvier, 1830) in terms of occurrence (%FO 20.7) and numbers (29.6%) respectively. The squid Loligo gahi (d'Orbigny, 1835) was the most frequent cephalopod prey (42.1%), whereas Octopus tehuelchus (d'Orbigny, 1834) was the most abundant (77%). The higher amount and diversity of prey found in the spring in comparison with the winter season might be related to a higher feeding activity of seals or to a seasonal increase in food availability in the area.

Contributions on Gargaphia (Heteroptera, Tingidae) systematics: redescriptions of two South American species with considerations on the status of G. inca

Gargaphia inca Monte, 1943 was synonymized with G. opima Drake, 1931 without any declared reasons. Gargaphia inca is known only from its type location (Satipo, Peru), and G. opima from Colombia (Villavencio) and Peru (Cam. Del Pichis, type-locality), in addition to the new records here presented, including the first record for Ecuador. Both species are redescribed, and the status of G. inca is revisited and raised from synonymy. Illustrations of some of the most remarkable differences between these taxa are provided, as well as dorsal habitus images. Discussions on the genus systematic status and this nomenclatural act are presented.

Proceedings of the Linnean Society of New South Wales.

v.1=[no.1-4] (1875-1877)

Proceedings of the Linnean Society of New South Wales.

v.2=[no.5-8] (1877-1878)

Proceedings of the Linnean Society of New South Wales.

v.6=[no.21-24] (1881-1882)

Proceedings of the Linnean Society of New South Wales.

v.22=no.85-88 (1897)

Proceedings of the Linnean Society of New South Wales.

[v.15]=[no.57-60] (1890-1891)

Proceedings of the Linnean Society of New South Wales.

v.41=no.161-164 (1916)

Proceedings of the Linnean Society of New South Wales.

v.36=no.141-144 (1911)

Freedom of choice as control over outcomes

As interactions between individuals are introduced into the freedom of choice literature by the mean of game forms, new issues appear. In particular, in this paper it is argued that individuals face uncertainty with respect to outcomes as they lose the control they implicitely exert over options in the opportunity set framework. A criterion is proposed as to compare alternative game forms in terms of the control they offer to individuals. The CardMin criterion suggests that any game form should be judged on the basis of the strategy offering the lowest number of pairwise different outcomes. An axiomatic characterization is provided in the case of two individuals.

What is the Causal Effect of Information and Learning about a Public Good on Willingness to Pay?

In this study we elicit agents’ prior information set regarding a public good, exogenously give information treatments to survey respondents and subsequently elicit willingness to pay for the good and posterior information sets. The design of this field experiment allows us to perform theoretically motivated hypothesis testing between different updating rules: non-informative updating, Bayesian updating, and incomplete updating. We find causal evidence that agents imperfectly update their information sets. We also field causal evidence that the amount of additional information provided to subjects relative to their pre-existing information levels can affect stated WTP in ways consistent overload from too much learning. This result raises important (though familiar) issues for the use of stated preference methods in policy analysis.