Using ecosystem-services assessments to determine trade-offs in ecosystem-based management of marine mammals

The goal of ecosystem-based management (EBM) is to support a sustainable and holistic multisectored management approach, and is recognized in a number of international policy frameworks. However, it remains unknown how these goals should be linked to assessments and management plans for marine fauna, such as mammals and fish stocks. It appears particularly challenging to carry out trade-off analyses of various ocean uses without a framework that integrates knowledge of environmental, social, and economic benefits derived from nonstationary marine fauna. We argue this gap can be filled by applying a version of the ecosystem-service approach at the population level of marine fauna. To advance this idea, we used marine mammals as a case study to demonstrate what indicators could operationalize relevant assessments and deliver an evidence base for the presence of ecosystem services and disservices derived from marine mammals. We found indicators covering common ecosystem service categories feasible to apply; examples of indicator data are already available in the literature for several populations. We encourage further exploration of this approach for application to marina fauna and biodiversity management, with the caveat that conceptual tensions related to the use of the ecosystem service concept itself needs to be addressed to ensure acceptance by relevant stakeholders.     

Seasonal variation in lipid class and fatty acid composition of two small copepods in Balsfjorden,northern Norway

Zooplankton were collected at Svartnes, northern Norway between 1985 and 1986. The lipid class and fatty acid composition of a subarctic population ofPseudocalanus acuspes (Giesbrecht, 1881) andAcartia longiremis Lilljeborg are described for four seasons of the year. The results are discussed in relation to the seasonal variation in abundance and dry weight of the predominant developmental stages. The lipid composition of these small copepod species resembles that of omnivorous or carnivorous species.P. acuspes andA. longiremis overwinter in a state of arrested development, but seem to feed actively throughout the year. This behaviour resembles that of the omnivoreMetridia longa (Lubbock), but is in contrast to that of the herbivoreCalanus finmarchicus (Gunnerus) from the same area, which spends the winter in diapause.     

Rebuilding after the tsunami: getting it right

The practice of integrated coastal management (ICM) has matured sufficiently since its beginnings in the early 1980s to suggest a set of principles that could be used to guide the massive investments that will be made over the next several years to rehabilitate and reconstruct the thousands of kilometers of coastlines devastated by the 26 December 2004 tsunami. We offer six principles to guide what can be done to make coastal communities less vulnerable, to improve the conditions of the poor, and to avoid repeating the mistaken judgements that have been made in the past about how shorelines are allocated and developed. We then offer a set of five principles to guide how action plans are formulated and implemented. These stress the critical importance of tailoring principles to the unique conditions and needs of each place. The roles of national government in setting policies to guide a decentralized planning and decision-making process are distinguished from a negotiation process that engages the people of the place in a bottom-up application of ICM good practices.     

In search of human-associated bacterial pathogens in Antarctic wildlife: report from six penguin colonies regularly visited by tourists

We investigated the potential role of Antarctic tourism in the introduction of human-associated pathogens into Antarctic wildlife. We collected and analyzed 233 fecal samples from eight bird species. The samples were collected at six localities on the Antarctic Peninsula, which often is visited by tourists. Every sample was investigated for pathogens of potential human origin: Campylobacter jejuni, Salmonella spp., and Yersina spp. None of these bacteria was found. Our data suggest that the tourism industry so far has achieved its goal of not introducing pathogens into the Antarctic region. There is, however, an urgent need to further investigate the situation in areas closer to permanent Antarctic settlements.     

Potential effects of forest policies on terrestrial biodiversity in a multi-ownership province.

We used spatial simulation models to evaluate how current and two alternative policies might affect potential biodiversity over 100 years in the Coast Ranges Physiographic Province of Oregon. This 2.3-million-ha province is characterized by a diversity of public and private forest owners, and a wide range of forest policy and management objectives. We evaluated habitat availability for seven focal species representing different life histories. We also examined how policies affected old-growth stand structure, age distributions relative to the historical range of variability, and landscape patterns of forest types. Under the current policy scenario, the area of habitat for old-growth forest structure and associated species increased over time, the habitat for some early-successional associates remained stable, and the area of hardwood vegetation and diverse early-successional stages declined. The province is projected to move toward but not reach the historical range of variation of forest age classes that may have occurred under the wildfire regimes of the pre-Euroamerican settlement period. Ownership explained much of the pattern of biodiversity in the province, and under the current policy scenario, its effect increased over time as the landscape diverged into highly contrasting forest structures and ages. Patch type diversity declined slightly overall but declined strongly within ownerships. Most of the modeled change in biodiversity over time resulted from policies on public forest lands that were intended to increase the area of late-successional forests and species. One of the alternative policies, increased retention of wildlife trees on private lands, reduced the contrast between ownerships and increased habitat availability over time for both early- and late-successional species. Analysis of another alternative, stopping thinning of plantations on federal lands, indicated that current thinning regimes improve habitat for the Olive-sided Flycatcher, but the no-thinning alternative had no effect on the habitat scores for the late-successional species in the 100-year simulation. A comparison of indicators of biological diversity suggests that using focal species and forest structural measures can provide complementary information on biodiversity. The multi-ownership perspective provided a more complete synthesis of province-wide biodiversity patterns than assessments based on single ownerships.     

Xanthoria parietina as a monitor of ground-level ambient ammonia concentrations

Total nitrogen in transplanted and in situ lichen thalli of Xanthoria parietina were related to ambient ammonia air concentrations measured with passive ALPHA (Adapted Low-cost Passive High Absorption) diffusion samplers in Denmark. Transplants and ALPHA samplers were exposed four months in a transect on heathland close to a pig farm. Monthly mean ammonia concentrations declined exponentially approaching background levels after 300 m. Nitrogen content of the lichen transplants tended to decline with distance, though only a few stations were significantly different from each other. Where ammonia concentrations were high, maximum content of nitrogen was reached after one month of exposure. Conversely, at sites with background concentrations, it took several months to reach a statistically significant uptake. The correlation between ammonia concentration in the air and in situ X. parietina was significant.     

Conservation, commercialisation and confusion: harvesting of Ischyrolepis in a coastal forest, South Africa

Harvesting of non-timber forest products is an integral component of rural livelihoods throughout the developing world. At times this is at odds with conservation objectives. Reconciliation of the two requires examination of local level contexts and needs. This paper reports on the harvesting needs for Ischyrolepis by a rural community in South Africa, against the setting that they had recently been prohibited from harvesting by the local conservation officials. Interviews were conducted with conservation officials to understand the reasoning for the prohibition. Local demand for Ischyrolepis was assessed by household surveys, as well as in-depth interviews with traders. The density and size class distribution of Ischyrolepis was determined using transects. The total annual demand for Ischyrolepis was determined to be approximately only 2.7% of the standing crop. The bulk of the annual demand was for small-scale trade, the income from which was a primary source of income for the few harvesters. Very little evidence could be found indicating that harvesting was damaging the resource or its habitat, and local knowledge suggested that the abundance of the species was stimulated by harvesting. Even if market demand were to increase, the size of the shoots required means that less than 20% of the standing crop could be harvested annually. Current regulations around harvesting are in a state of revision, and hence confusion prevails regarding if harvesting is permissible, and if so, under what conditions, which is detrimental to both conservation and livelihoods. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.     

Feeding and assimilation kinetics of Artemia franciscana fed Isochrysis galbana (clone T. Iso)

Artemia franciscana was grown on Isochrysis galbana Green (clone T. Iso) at saturated food concentrations (13 to 20 mg C l⁻¹) for 11 d at 26 to 28 °C, and 34 ppt salinity. Three groups of brine shrimp were used in the feeding experiments: metanauplius III and IV (Group 1), post-metanauplius II and III (Group 2) and post-metanauplius VIII (Group 3), corresponding to 4-, 7- and 11-d-old animals, respectively. The ingestion rate, clearance rate and carbon balance were estimated for these stages at different concentrations of ¹⁴C-labeled I. galbana ranging from 0.05 to 30 mg C l⁻¹. The handling time of algae was determined for all three groups. The ingestion rate (I, ng C ind⁻¹ h⁻¹) increased as a function of animal size and food concentration. In all three groups, the ingestion rate increased to a maximum level (I _max) and remained constant at food concentrations ≥10 mg C l⁻¹ (saturated food concentrations). The clearance rate (CR, μl ind⁻¹ h⁻¹) increased with increasing food concentration up to a maximum rate (CR _max), after which it decreased for even higher food concentrations. The functional response of A. franciscana was most consistent with Holling's Type 3 functional response curve (sigmoidal model), which for the two oldest groups (Group 2 and 3) differed significantly from a Type 2 response (p < 0.05). The gut passage time for the three groups of A. franciscana, feeding on saturated food concentration (20 mg C l⁻¹), varied between 24 and 29 min. As the nauplii developed to pre-adult stage the handling time of the algae increased as a function of animal size. The assimilation rate (ng C ind⁻¹ h⁻¹) in the youngest stages (Group 1 and 2) increased with increasing food concentrations, reaching a maximum level close to 10 mg C l⁻¹. At higher food concentrations the assimilation rate decreased, and the proportions of defecated carbon increased, reaching 60 to 68% in the post-metanauplius stages (Group 3). The assimilation efficiency (%) was high at the lowest food concentrations in all three groups (89 to 64%). At higher concentrations, the assimilation efficiency decreased, reaching 56 to 38% at the highest concentrations. Received: 2 February 2000 / Accepted: 25 March 2000     

Predictors of specialist avifaunal decline in coastal marshes

Coastal marshes are one of the world's most productive ecosystems. Consequently, they have been heavily used by humans for centuries, resulting in ecosystem loss. Direct human modifications such as road crossings and ditches and climatic stressors such as sea‐level rise and extreme storm events have the potential to further degrade the quantity and quality of marsh along coastlines. We used an 18‐year marsh‐bird database to generate population trends for 5 avian species (Rallus crepitans, Tringa semipalmata semipalmata, Ammodramus nelsonii subvirgatus, Ammodramus caudacutus, and Ammodramus maritimus) that breed almost exclusively in tidal marshes, and are potentially vulnerable to marsh degradation and loss as a result of anthropogenic change. We generated community and species trends across 3 spatial scales and explored possible drivers of the changes we observed, including marsh ditching, tidal restriction through road crossings, local rates of sea‐level rise, and potential for extreme flooding events. The specialist community showed negative trends in tidally restricted marshes (?2.4% annually from 1998 to 2012) but was stable in unrestricted marshes across the same period. At the species level, we found negative population trends in 3 of the 5 specialist species, ranging from ?4.2% to 9.0% annually. We suggest that tidal restriction may accelerate degradation of tidal marsh resilience to sea‐level rise by limiting sediment supply necessary for marsh accretion, resulting in specialist habitat loss in tidally restricted marshes. Based on our findings, we predict a collapse of the global population of Saltmarsh Sparrows (A. caudacutus) within the next 50 years and suggest that immediate conservation action is needed to prevent extinction of this species. We also suggest mitigation actions to restore sediment supply to coastal marshes to help sustain this ecosystem into the future.