Predicting population dynamics of weed biological control agents: science or gazing into crystal balls?

Various factors can influence the population dynamics of phytophages post introduction, of which climate is fundamental. Here we present an approach, using a mechanistic modelling package (CLIMEX), that at least enables one to make predictions of likely dynamics based on climate alone. As biological control programs will have minimal funding for basic work (particularly on population dynamics), we show how predictions can be made using a species geographical distribution, relative abundance across its range, seasonal phenology and laboratory rearing data. Many of these data sets are more likely to be available than long-term population data, and some can be incorporated into the exploratory phase of a biocontrol program. Although models are likely to be more robust the more information is available, useful models can be developed using information on species distribution alone. The fitted model estimates a species average response to climate, and can be used to predict likely geographical distribution if introduced, where the agent is likely to be more abundant (i.e. good locations) and more importantly for interpretation of release success, the likely variation in abundance over time due to intra- and inter-year climate variability. The latter will be useful in predicting both the seasonal and long-term impacts of the potential biocontrol agent on the target weed. We believe this tool may not only aid in the agent selection process, but also in the design of release strategies, and for interpretation of post-introduction dynamics and impacts. More importantly we are making testable predictions. If biological control is to become more of a science making and testing such hypothesis will be a key component.

When do conservation planning methods deliver? Quantifying the consequences of uncertainty

The rapid global loss of biodiversity has led to a proliferation of systematic conservation planning methods. In spite of their utility and mathematical sophistication, these methods only provide approximate solutions to real-world problems where there is uncertainty and temporal change. The consequences of errors in these solutions are seldom characterized or addressed. We propose a conceptual structure for exploring the consequences of input uncertainty and oversimpli?ed approximations to real-world processes for any conservation planning tool or strategy. We then present a computational framework based on this structure to quantitatively model species representation and persistence outcomes across a range of uncertainties. These include factors such as land costs, landscape structure, species composition and distribution, and temporal changes in habitat. We demonstrate the utility of the framework using several reserve selection methods including simple rules of thumb and more sophisticated tools such as Marxan and Zonation. We present new results showing how outcomes can be strongly affected by variation in problem characteristics that are seldom compared across multiple studies. These characteristics include number of species prioritized, distribution of species richness and rarity, and uncertainties in the amount and quality of habitat patches. We also demonstrate how the framework allows comparisons between conservation planning strategies and their response to error under a range of conditions. Using the approach presented here will improve conservation outcomes and resource allocation by making it easier to predict and quantify the consequences of many different uncertainties and assumptions simultaneously. Our results show that without more rigorously generalizable results, it is very dif?cult to predict the amount of error in any conservation plan. These results imply the need for standard practice to include evaluating the effects of multiple real-world complications on the behavior of any conservation planning method.

Data S1. Results of the analyses considering developmental time, supplementary figures and tables & Video S1

Our ability to project the impact of global change on marine ecosystem is limited by our poor understanding on how to predict species sensitivity. For example, the impact of ocean acidification is highly species-specific, even in closely related taxa. The aim of this study was to test the hypothesis that the tolerance range of a given species to decreased pH corresponds to their natural range of exposure. Larvae of the green sea urchin Strongylocentrotus droebachiensis were cultured from fertilization to metamorphic competence (29 days) under a wide range of pH (from pHT = 8.0/pCO2 ~ 480 ?atm to pHT = 6.5/pCO2 ~ 20 000 ?atm) covering present (from pHT 8.7 to 7.6), projected near-future variability (from pHT 8.3 to 7.2) and beyond. Decreasing pH impacted all tested parameters (mortality, symmetry, growth, morphometry and respiration). Development of normal, although showing morphological plasticity, swimming larvae was possible as low as pHT >= 7.0. Within that range, decreasing pH increased mortality and asymmetry and decreased body length (BL) growth rate. Larvae raised at lowered pH and with similar BL had shorter arms and a wider body. Relative to a given BL, respiration rates and stomach volume both increased with decreasing pH suggesting changes in energy budget. At the lowest pHs (pHT <= 6.5), all the tested parameters were strongly negatively affected and no larva survived past 13 days post fertilization. In conclusion, sea urchin larvae appeared to be highly plastic when exposed to decreased pH until a physiological tipping point at pHT = 7.0. However, this plasticity was associated with direct (increased mortality) and indirect (decreased growth) consequences for fitness.

Benthic foraminiferal abundances in Late Cretaceous sediments of the Tethys

Benthic foraminiferal distribution patterns throughout the late Maastrichtian Tethyan deep sea are analyzed. Many species are ubiquitously distributed throughout this region and therefore it is hard to assess their ecological preferences. However, five species show distribution patterns, which suggest that they may have distinctive paleoenvironmental preferences. These preferences are interpreted from hypothesized surface circulation and upwelling patterns. Additional information comes from Recent benthic foraminiferal ecology and from responses to the Cretaceous/Paleogene (k/Pg) boundary event. This enables us to assess the ecological preferences of these late Maastrichtian taxa, and establish them as ecological-marker (ecomarker) species for paleoenvironmental interpretation of the late Maastrichtian bathyal-abyssal Tethyan realm. (1) Eouvigerina subsculpturu is suggested to be indicative of reasonably oxygenated upper-middle bathyal environments, though with high abundance of utilizable organic matter. (2) Sliteria varsoviensis is linked to areas of late Maastrichtian upwelling and seems to have been an epibenthic species with an opportunistic life mode. (3) Guvelinellu beccuriiformis and (4) Nuttullides truempyi are considered to be indicative of oligotrophic conditions unless they occur with a large proportion of endobenthic morphotypes. (5) Guvelinellu pertusu is proposed to indicate neritic-middle bathyal environments of the 'boreal' realm, which might be influenced by more seasonal food-fluxes and by higher oxygen levels than similar settings in the (sub)tropics. Finally, the anomalous high abundances of the buliminid species Sitella cf. plunu in deep open ocean environments is discussed in terms of possible mechanisms permitting such a (morphologically) opportunistic species to thrive in such an assumedly oligotrophic environment.

The relationship between vegetation and modern pollen assemblages on Mount Paggeo (NE Greece)

In this study, we investigated the relationship between vegetation and modern-pollen rain along the elevational gradient of Mount Paggeo. We apply multivariate data analysis to assess the relationship between vegetation and modern-pollen rain and quantify the representativeness of forest zones. This study represents the first statistical analysis of pollen-vegetation relationship along an elevational gradient in Greece. Hence, this paper improves confidence in interpretation of palynological records from north-eastern Greece and may refine past climate reconstructions for a more accurate comparison of data and modelling. Numerical classification and ordination were performed on pollen data to assess differences among plant communities that beech (Fagus sylvatica) dominates or co-dominates. The results show a strong relationship between altitude, arboreal cover, human impact and variations in pollen and nonpollen palynomorph taxa percentages.

The bottom trawl survey of Lake Victoria, Uganda in July to August 2003

The objective of the bottom trawl survey in July/August 2003, was to monitor the changes in the fish stocks in the Uganda sector of Lake Victoria with particular emphasis on species composition, distribution, abundance and population structure.

Serviços dos ecossistemas prestados pelos estuários : especiação e capacidade de retenção do fósforo

O fator nutricional presente nos sapais não é só importante para os organismos que nele habitam como também apresenta uma importância ecológica a uma maior escala. Exemplifica-se este fato com a capacidade de retenção do Fósforo (P) por parte das plantas podendo estas competir como produto químicos para sua imobilização através da incorporação da sua fração biodisponível para cumprimento dos mecanismos básicos de sobrevivência. O rizosedimento dessas plantas é uma importante fonte de nutrientes necessários para garantia básica da perpetuação de todos os serviços (regulação, provisão, cultural) gerados pelo ambiente. A perda de áreas de sapal foi o motivo principal para a elaboração desta tese visto a preocupação em relação aos impactes que a perda de serviços associados à área de estudo escolhida, o sistema lagunar da Ria de Aveiro, poderá vir sofrer caso aconteçam alterações hídricas (naturais ou antrópicas) mais acentuadas no futuro. Essa tese assume como compromisso chamar a atenção para essa questão como também investigar os mecanismos do ciclo do P este importante nutriente considerado essencial para a manutenção da vida em nosso planeta. Para este estudo foram escolhidas 3 espécies de plantas halófitas representantes do sapal amostral, são elas: Bolbochenous maritimus, Spartina maritima e de Juncus maritimus. As questões levantadas buscam compreender o papel do P nas transformações que ocorrem no rizosedimento das halófitas em 3 diferentes contextos: (i) quando comparados os valores da biomassa de P associado às halófitas estudadas (estudo realizado nos sapais povoados por Spartina maritima e Juncus maritimus) em toda extensão da Ria de Aveiro (ii) quando da disponibilidade de P perante a presença de poluentes inorgânicos no Largo do Laranjo, que corresponde a uma zona historicamente contaminada por metais (estudo realizado no rizosedimento das espécies Bolbochenous maritimus e Juncus maritimus) e (iii) quanto à intrusão superficial da água salgada da laguna (estudo focado na avaliação da perda do P próximo às raízes das halófitas que habitam a zona externa do dique do Baixo Vouga Lagunar (BVL) que corresponde à zona de confluência do Rio Vouga com a Ria de Aveiro). Por meio da análise do rizosedimento e da biomassa das diferentes halófitas predominantes do sapal foi possível verificar que, em relação à carga nutritiva fosfática, de Norte (Canal de São Jacinto/Ovar) a Sul (Canal de Mira) da Ria de Aveiro, a cota do sapal é mais importante do que a natureza espacial do sistema. Esta informação é primordial para a assertividade de futuras medidas de criação e reabilitação das áreas de sapal na Ria de Aveiro. Os estudos realizados nas áreas impactadas (Largo do Laranjo e BVL) incidiram na análise do perfil vertical rizosedimentar das halófitas pertencentes ao sapal médio-alto. Estes estudos revelaram que o rizosedimento dessas halófitas possui características peculiares que definem a dinâmica do ciclo do P de forma bastante característica. O rizosedimento das halófitas presentes no Largo do Laranjo apresentaram teores biodisponíveis de P equivalentes àqueles presentes no rizosedimento de área mais afastada da fonte pontual de contaminação para as mesmas espécies. Numa visão otimista, os resultados revelam que ambos sapais, Largo de Laranjo e Cais do Bico, apresentam condições equiparável para perpetuação dos serviços por eles gerados, que nesse caso se tornam ainda mais valiosos devido a garantia da fitoestabilização dos contaminantes (prevenção da entrada de contaminantes na coluna d’água e na cadeia alimentar). No Baixo Vouga Lagunar a análise espacial do sapal na zona exterior ao dique revelou a perda da diversidade das espécies bem como o aumento da área de vasa e consequentemente a perda dos teores de P associados ao rizosedimento das halófitas mais expostas aos efeitos da compressão costeira intensificados pelas ações naturais e antrópicas a que a Ria está sujeita. Em geral, a degradação dessa área de sapal devido aos fenômenos de assoreamento ou de erosão não pode ser separada dos processos sedimentares na área envolvente, principalmente no caso da Ria de Aveiro que tem sofrido constantes mudanças para atender às necessidades das atividades humanas. Essa tendência provavelmente não mudará no futuro próximo. Consequentemente, a evolução da laguna será principalmente dependente do resultado direto das ações humanas que deverão sempre encontrar formas de compensar os danos causados no âmbito de intervenções de reabilitação do sistema hídrico. A recriação de áreas de sapal pode ter lugar como medida mitigadora no âmbito de intervenções de reabilitação de áreas degradadas e ainda poderá servir como forma de captura de P para programas de utilização de fertilizantes naturais (componente desejável para a agricultura moderna o que é particularmente importante para as regiões altamente dependentes do mercado de importação). Deste modo, recomenda-se que a recuperação das áreas de sapal seja enquadrada no âmbito de intervenções mais amplas de valorização dos sistemas estuarinos e lagunares.

Projeto raia de fogo: aspectos populacionais da raia de fogo (Dasyatis marianae Gomes, Rosa & Gadig, 2000) e pesca de elasmobrânquios no complexo recifal do Parracho de Maracajaú

The species Dasyatis marianae inhabits coastal areas associated with coral reefs, considered endemic to the northeast of Brazil, occurring from the State of Maranhão to the south of Bahia. Specimens of this species are commonly sighted by divers and fishermen in the area of Maracajaú reefs, a complex reef that is part of the Environmental Protection Area of Coral Reefs (EPACR), which was developed in this study about the ecology and biology of the D. marianae, in order to characterize aspects of population structure in the area of the reef complex of Parracho de Maracajaú. We analyzed 120 specimens caught by artisanal fishing site of the size, weight, sex, stage of maturity and stomach contents. Most subjects were adult males (1.7:1) and was more abundant for rays with lengths between 25 and 29cm of LD, where females reach larger sizes, a feature common to other rays. The largest specimens were captured in the area of seagrass, which is preferred for the species. The distribution of species in the area showed an ontogenetic and sexual segregation, where the youthful occur near the beach, which is a likely area for nursery and growth of the adult females prevail in the seagrass, which apparently has a high prey availability, and Adult males are more distant, a higher proportion occurring in outlying areas, suggesting a habit more exploratory than the females. The evaluation of the reproductive system indicated 3 reproductive cycles per year, one young per pregnancy, and showed that the mature males were smaller than females. The cubs of D. marianae size at birth 12 to 15cm LD. As for diet, the species was characterized as carnivorous crustacean specialist. The performance of visual censuses in different localities allowed to evaluate the density of D. marianae in different environments of the complex. The species occurs in greater numbers in seagrass, environment very important for the conservation of the species. 100 individuals of D. marianae marked in reef complex area enrolled in a recapture rate of 3%. Some behavioral aspects were evaluated, as diurnal pattern of activity, interaction with cleaning and fish Pomacanthus paru followers as Lutjanus analis and Carangoides bartholomaei. Overall, much of the information obtained should be used for management of the species

Role of climate on barn owls road-kill likelihood and the effect on population viability in future climate change

Roads represent a new source of mortality due to animal-vehicle risk of collision threatening log-term populations’ viability. Risk of road-kill depends on species sensitivity to roads and their specific life-history traits. The risk of road mortality for each species depends on the characteristics of roads and bioecological characteristics of the species. In this study we intend to know the importance of climatic parameters (temperature and precipitation) together with traffic and life history traits and understand the role of drought in barn owl population viability, also affected by road mortality in three scenarios: high mobility, high population density and the combination of previous scenarios (mixed) (Manuscript). For the first objective we correlated the several parameters (climate, traffic and life history traits). We used the most correlated variables to build a predictive mixed model (GLMM) the influence of the same. Using a population model we evaluated barn owl population viability in all three scenarios. Model revealed precipitation, traffic and dispersal have negative relationship with road-kills, although the relationship was not significant. Scenarios showed different results, high mobility scenario showed greater population depletion, more fluctuations over time and greater risk of extinction. High population density scenario showed a more stable population with lower risk of extinction and mixed scenario showed similar results as first scenario. Climate seems to play an indirect role on barn owl road-kills, it may influence prey availability which influences barn owl reproductive success and activity. Also, high mobility scenario showed a greater negative impact on viability of populations which may affect their ability and resilience to other stochastic events. Future research should take in account climate and how it may influence species life cycles and activity periods for a more complete approach of road-kills. Also it is important to make the best mitigation decisions which might include improving prey quality habitat.

Projeto raia de fogo: aspectos populacionais da raia de fogo (Dasyatis marianae Gomes, Rosa & Gadig, 2000) e pesca de elasmobrânquios no complexo recifal do Parracho de Maracajaú

The species Dasyatis marianae inhabits coastal areas associated with coral reefs, considered endemic to the northeast of Brazil, occurring from the State of Maranhão to the south of Bahia. Specimens of this species are commonly sighted by divers and fishermen in the area of Maracajaú reefs, a complex reef that is part of the Environmental Protection Area of Coral Reefs (EPACR), which was developed in this study about the ecology and biology of the D. marianae, in order to characterize aspects of population structure in the area of the reef complex of Parracho de Maracajaú. We analyzed 120 specimens caught by artisanal fishing site of the size, weight, sex, stage of maturity and stomach contents. Most subjects were adult males (1.7:1) and was more abundant for rays with lengths between 25 and 29cm of LD, where females reach larger sizes, a feature common to other rays. The largest specimens were captured in the area of seagrass, which is preferred for the species. The distribution of species in the area showed an ontogenetic and sexual segregation, where the youthful occur near the beach, which is a likely area for nursery and growth of the adult females prevail in the seagrass, which apparently has a high prey availability, and Adult males are more distant, a higher proportion occurring in outlying areas, suggesting a habit more exploratory than the females. The evaluation of the reproductive system indicated 3 reproductive cycles per year, one young per pregnancy, and showed that the mature males were smaller than females. The cubs of D. marianae size at birth 12 to 15cm LD. As for diet, the species was characterized as carnivorous crustacean specialist. The performance of visual censuses in different localities allowed to evaluate the density of D. marianae in different environments of the complex. The species occurs in greater numbers in seagrass, environment very important for the conservation of the species. 100 individuals of D. marianae marked in reef complex area enrolled in a recapture rate of 3%. Some behavioral aspects were evaluated, as diurnal pattern of activity, interaction with cleaning and fish Pomacanthus paru followers as Lutjanus analis and Carangoides bartholomaei. Overall, much of the information obtained should be used for management of the species

Review of the Psychodinae from Mallorca, Spain, with description of Pericoma unipennata, sp. n. (Diptera, Psychodidae)

We review the Psychodinae of Mallorca, recognising fifteen species based on recent collections and available literature. Previously unpublished data is presented for eleven species, of which Neoarisemus ibericus Wagner, 1978, Mormia tenebricosa (Vaillant, 1954), Clogmia albipunctata (Williston, 1893), Lepiseodina rothschildi (Eaton, 1913), Paramormia ustulata (Walker, 1856), Philosepedon pyrenaicus Vaillant, 1974 and Psychoda (Psycha) grisescens Tonnoir, 1922 are first records for Mallorca. An old record of Pericoma trifasciata (Meigen, 1804) is considered doubtful. Pericoma unipennata sp. n is described and illustrated based on a male collected at Deía. Distributional data are reviewed for all newly recorded species. Based on the Psychodinae fauna, the zoogeographical affinities of Mallorca are briefly discussed.

Ascidonia Flavomaculata (Heller, 1864), a new record for the Portuguese marine invertebrate fauna (Decapoda, Pontoniidae)

Several specimens of Ascidonia flavomaculata were collected during experimental fishing trials along the southern coast of Portugal. All specimens were associated with the solitary ascidian, Phallusia mammillata. The pontoniinae shrimp, A. flavomaculata is here recorded from the Portuguese coast for the first time, extending the species’ known distribution range further north along the coast of the eastern Atlantic Ocean.

Determining conservation priority areas for Palearctic passerine migrant birds in sub-Saharan Africa

Migratory bird species breeding in the Palearctic and overwintering in sub-Saharan Africa face multiple conservation challenges. As a result, many of these species have declined in recent decades, some dramatically. We therefore used the best available database for the distribution of 68 passerine migrants in sub-Saharan Africa to determine priority regions for their conservation. After modeling each species’ distribution using BIOMOD software, we entered the resulting species distributions at a 1° × 1° grid resolution into MARXAN software. We then used several different selection procedures that varied the boundary length modifier, species penalty factor, and the inclusion of grid cells with high human footprint and with protected areas. While results differed between selection procedures, four main regions were regularly selected: (1) one centered on southern Mali; (2) one including Eritrea, central Sudan, and northern Ethiopia; (3) one encompassing southwestern Kenya and much of Tanzania and Uganda; and (4) one including much of Zimbabwe and southwestern Zambia. We recommend that these four regions become priority regions for research and conservation efforts for the bird species considered in this study.