Testing the robustness of primary production models in shallow coastal areas: a case study

In this paper we investigate the robustness of a dynamic model, which describes the dynamic of the seagrass Zostera marina, with respect to the inter-annual variability of the two main forcing functions of primary production models in eutrophicated environments. The model was previously applied to simulate the seasonal evolution of this species in the Lagoon of Venice during a specific year and calibrated against time series of field data. In the this paper, we present and discuss the results which were obtained by forcing the model using time series of site-specific daily values concerning the solar radiation intensity and water temperature. The latter was estimated by means of a regression model, whose input variable was a site-specific time series of the air temperature. The regression model was calibrated using a year-long time series of hourly observations. The Z marina model was first partially recalibrated against the same data set that was used in the original paper. Subsequently, the model was forced using a 7-year-long time series of the driving functions, in order to check the reliability of its long-term predictions. Even though the calibration gave satisfactory results, the multi-annual trends of the output variables were found to be in contrast with the observed evolution of the seagrass biomasses. Since detailed information about the air temperature and solar radiation are often available, these findings suggest that the testing of the ecological consistency of the evolution of primary production models in the long term would provide additional confidence in their results, particularly in those cases in which the scarcity of field data does not allow one to perform a formal corroboration/validation of these models

Evaluation of management factors affecting the relative success of a Brook Trout eradication program using YY male fish and electrofishing suppression

Removal of non-native fish populations can be crucial to the conservation of native species, but often presents a complex challenge for managers. The goal of Trojan Y chromosome (TYC) programs is to skew the non-native sex ratio until only males remain, leading to eradication. We present results from a simulation model used to explore effects of alternative management approaches on an in-progress mechanical removal and TYC program to eradicate non-native Brook Trout. Simulation results indicated that stocking fingerling YY males (~137 mm) was more effective than stocking catchable-sized YY males (~230 mm), although questions about inter-cohort competition warrant further investigation. Increasing the proportion of mature fingerling YY males reduced treatment time by increasing the number of YY male spawners and increasing density-dependent mortality on young, mature wild Brook Trout. Maximizing the spatial distribution of YY male releases may be crucial to program success but is also dependent upon immediate dispersal movements. Principles derived from our results can be broadly applied to the management of other aquatic invaded systems using TYC programs to eradicate non-native species.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Institutionalising Adaptive Management: Creating a Culture of Learning in New South Wales Parks and Wildlife Service

‘Learn by doing’ is the mantra of adaptive management. Organisations that undertake conservation management are often challenged by high levels of uncertainty and a multiplicity of competing priorities leading to more doing than learning. Adaptive management provides a sound approach for these organisations to effectively manage uncertainty and ambiguity. However, institutional characteristics can impede the development of a learning culture and thus the uptake of adaptive management. Following on from a major review of the organisation's performance, the New South Wales National Parks and Wildlife Service (NPWS), responsible for managing over 6,5000,000 ha and over 750 protected areas, embarked on an ambitious program to introduce a performance management program based on adaptive management principles and to institutionalise it so that it became an indelible part of the way NPWS undertakes conservation. Through the combination of an adaptive management framework, a comprehensive performance evaluation program and set of common denominators defining the services provided in the organisation, NPWS has evolved its approach to ensure maximum penetration and uptake of the adaptive management ethos, by actively influencing key institutional facets such as policy, planning regimes, programs, projects and systems to link and align them, and ultimately to help close the adaptive management loop. While adaptive management is becoming normalised in NPWS, future efforts will be geared towards making the institutionalisation of adaptive management more robust and permanent