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Aim: Understanding patterns and drivers of biodiversity are essential towards developing effective conservation strategies for shallow marine habitats broadly. However, little is known about the natural and anthropogenic factors that structure fish biodiversity of sandy beaches, one of the largest and most socio‐economically valuable nearshore habitats due to their endemic fauna, economic importance and cultural relevance. Here, we investigated how environmental variables and urbanization affect taxonomic and functional diversity of nearshore fish assemblages to provide general biodiversity patterns that can serve as baseline information for management plans when considering conservation prioritization. Location: Southeast Brazil. Methods: We surveyed fish communities at 77 sites along 150 km of coastline with different natural features and degrees of human influence using a combination of seine nets and surf‐BRUVS. We used generalized additive models (GAMs) to investigate the influence of environmental variables and urbanization on taxonomic and functional diversity of resident fish assemblages. Main results: We found that significant breaker wave height was the most important environmental variable in explaining the taxonomic and functional diversity of fish assemblages. The effects of increasing wave height were mostly negative, except for piscivorous fishes, which were most abundant at high energy sites, and for benthic and zoobenthivorous species, which were most abundant at sites with intermediate wave exposure. The latter species were also associated with higher chlorophyll‐a contributing to increased taxonomic richness and abundance. Further, anthropogenic impacts generally reduced diversity, with highest diversity only observed at the most pristine sites. Main conclusions: Our results demonstrate that both natural environmental variation and human activities structure the fish assemblages of sandy beach surf zones, affecting species that possess specific functional traits differently. These drivers should therefore be considered simultaneously in appointing protected areas in order to preserve a diversity of organisms and functional traits integral to productive beach ecosystems. [ABSTRACT FROM AUTHOR]

The globally accelerating environmental crisis calls for radical changes in the governance of ocean resources towards a more sustainable and socially equitable world. Transdisciplinary sustainability research and networked knowledge-to-action approaches are critical parts of this change. The effective application of such approaches still puzzles social actors (individuals and networks) willing to act in more transformative ways. We conducted twelve participatory network mapping activities to assess the perception of high-level federal government institutional entrepreneurs on the structure and dynamics of an emerging socio-political arena for marine spatial planning (MSP) in Brazil. Our informants, mostly cognizant of their own intra-governmental structures, anticipate the MSP arena to remain self-enclosed, with changes only occurring within the federal government structures in the coming years. Their perceptions were largely conservative, narrow, and unambitious and therefore unfit to generate regime transformations. The limited awareness of response capacities beyond the federal government potentially leads to the endurement of the low performance already present in the MSP arena. Results from the participatory network mapping informed a five-step functional ocean governability analysis pointing to key potential contributions to support a critical turn in MSP: 1. envision situated interactional narratives to leverage regime shifts; 2. build a shared understanding of and anticipating transformative coevolutionary dynamics; 3. build awareness of the potential synergies among disparate but innovative area-based responses; 4. specify inter-network-based limitations and the necessary changes underpinning potential leaps in performance levels of ocean governance orders; 5. make power asymmetries explicit to stir structurally tailored strategic action by less influential groups. We discuss the potential role of inter-network strategies and actions and how they may confront the symptoms of depoliticized MSP pathways and the risks of it becoming an instrument of further marginalisation and power asymmetry in Brazil. [ABSTRACT FROM AUTHOR]

Parasitism by isopods is a common phenomenon in marine fishes and may induce negative effects, especially in juvenile stages. The surf-zones of sandy beaches are an important nursery habitat for many fish species, including commercially important ones, and are structured by beach characteristics and human activities, which are suggested to influence the fishes' susceptibility to parasitism. Here, we analyze the early infestation and prevalence of parasitism in surf zones fishes of 27 beaches in southeastern Brazil with different characteristics. Parasites were recorded in only seven of the beaches. A high infestation was found in a single site, the highly urbanized Itaguá beach, where the prevalence of parasitism on juveniles and early adults of the Atlantic anchoveta Cetengraulis edentulus was high (68.11%). Four species of parasitic isopods were found, all belonging to the Cymothoidae family, but Livoneca desterroensis was the most abundant (78.7%). No effects of parasitism were detected on the size, weight and physiological condition of fishes, but presence of parasites and prevalence of infestation were positively affected by urbanization. Overall, our results indicate that the surf-zones have low parasite infestation, yet, they suggest that anthropic effects such as urbanization may enhance the prevalence of isopod parasitism. [ABSTRACT FROM AUTHOR]

The concept of institutional interplay (i.e., the interaction between institutions) is critical if the challenges to multilevel governance are to be better understood and addressed. Drawing on the literature on institutional interplay, this paper develops an analytical approach to examine challenges to multilevel coastal governance. São Paulo Macrometropolitan region (MMP, in Portuguese) is used to ground the empirical analysis. The macrometropolitan is one of the largest urban areas in the Southern Hemisphere; it houses the Metropolitan Region of São Paulo—one of the six most significant in the world. The MMP concentrates critical infrastructure, such as ports, airports, and roads, and considerable knowledge, technology, and innovation hubs. The coastal governance in the MMP area characterizes a highly connected multilevel system formed by 60 organizations (7 international, 29 national, 11 state, and 13 local). These comprised a complex environment featuring a great deal of fragmentation, and, consequently, jurisdictional and functional gaps and overlaps. This case was best described in terms of normative, functional, and political interplay. Interplay management has the potential to improve governance on the cross-level interactions among scale-dependent institutions of the MMP, enhancing synergies, and minimizing tensions among the institutions analyzed. This includes fostering cognitive interaction (i.e., promoting interinstitutional learning and assistance, and enhancing synergy) between institutions with complementary and/or similar objectives. Ultimately, interplay management may reduce fragmentation, improve compliance and monitoring, and increase cost-effectiveness. The findings from this paper may prove useful to other jurisdictions where pressing environmental issues involve multiple governance levels and interacting institutions. [ABSTRACT FROM AUTHOR]

Olivella minuta is an abundant neogastropod on sandy beaches from Texas (USA) to southern Brazil. This study aimed to characterize and compare the feeding activity and diet of a Brazilian population of O. minuta in different tidal zones (intertidal and subtidal), and different tidal levels (high and low tides), with three combinations of tidal zone and level being studied (intertidal during low tide, intertidal during high tide and subtidal). The results showed that diet composition was generally similar among tidal conditions, with O. minuta being a generalist, feeding on 45 different food items. Feeding activity, however, was higher in the intertidal during low tide, whereas the richness and diversity of food items were higher in the intertidal during high tide. The higher feeding activity of O. minuta during low tide may be linked to a lower risk of predation; at low tide organisms may be able to feed for a longer time, and this may be particularly true on beaches with fine sand, where water retention is higher than that on beaches with coarse sand. The higher diversity of food items consumed in the intertidal during high tide is likely related to the increased prevalence of planktonic food during high tide. Our results indicate that tidal zone and level may strongly influence the feeding activity of coastal soft-bottom species and that species may show higher feeding activity during low tide. Given the current loss of intertidal habitats due to anthropogenic activity and climate-change associated factors, our study has important implications, highlighting the importance of intertidal areas for the ecology and conservation of sandy beach species. [ABSTRACT FROM AUTHOR]

The loss of canopy‐forming seaweeds from urbanized coasts has intensified in response to warming seas and non‐climatic pressures such as population growth and declining water quality. Surprisingly, there has been little information on the extent of historical losses in the South‐western Atlantic, which limits our ability to place this large marine ecosystem in a global context. Here, we use meta‐analysis to examine long‐term (1969–2017) changes to the cover and biomass of Sargassum spp. and structurally simple algal turfs along more than 1,000 kilometres of Brazil's warm temperate coastline. Analysis revealed major declines in canopy cover that were independent of season (i.e., displaying similar trends for both summer and winter) but varied with coastal environmental setting, whereby sheltered bays experienced greater losses than coastal locations. On average, covers of Sargassum spp. declined by 2.6% per year, to show overall losses of 52% since records began (ranging from 20% to 89%). This contrasted with increases in the cover of filamentous turfs (24% over the last 27 years) which are known to proliferate along human‐impacted coasts. To test the relative influence of climatic versus non‐climatic factors as drivers of this apparent canopy‐to‐turf shift, we examined how well regional warming trends (decadal changes to sea surface temperature) and local proxies of coastal urbanization (population density, thermal pollution, turbidity and nutrient inputs) were able to predict the changes in seaweed communities. Our results revealed that the most pronounced canopy losses over the past 50 years were at sites exhibiting the greatest degree of coastal warming, the highest population growth and those located in semi‐enclosed sheltered bays. These findings contribute knowledge on the drivers of canopy loss in the South‐western Atlantic and join with global efforts to understand and mitigate declines of marine keystone species. [ABSTRACT FROM AUTHOR]

Monitoring and assessment of marine litter requires multi-stakeholder involvement at national and subnational levels. Collaborative governance approaches are important, but often fail without adequate effort towards identifying and engaging stakeholders with appropriate profiles for the issue at stake. Stakeholder Analysis (SA) is increasingly used to ensure efficient governance arrangements. Our hypothesis is that SA contributes to collaborative governance processes for marine litter policies. We explored a pioneer participatory process in Brazil, where SA was applied to identify, categorize, and prioritize stakeholders, and analyze their power and interest, for the Strategic Plan for Monitoring and Assessing Marine Litter in the state of São Paulo. A top-down/bottom-up approach revealed that snowball sampling complemented the stakeholder assemblage identified by the consultation of experts. Prioritization of data-related stakeholders streamlined the participatory process. The interest-power matrix evaluated stakeholders' influences, guiding specific engagement strategies. We highlight the significance of SA in collaborative governance and mobilizing key stakeholders for effective marine litter monitoring initiatives, contributing to the global agenda to combat marine pollution. [Display omitted] • We firstly applied Stakeholder Analysis (SA) to marine litter monitoring governance. • Bottom-up complemented top-down approaches to effectively map multi-stakeholders. • Power analysis revealed actors' influence and potential roles in the monitoring agenda. • Assessment of actors' interest level subsidizes future engagement efforts. • We recommend global monitoring governance schemes to implement a broad SA strategy. [ABSTRACT FROM AUTHOR]

Abstract Coastal embayed areas are important sites for many benthic and nektonic organisms that are being increasingly threatened by habitat degradation. The knowledge on the biology of these organisms can reveal the importance of such areas for their life cycles. Furthermore, population information is also imperative to recognize the importance of these species to structure coastal ecosystems and to provide support to management strategies. In this study, we aimed to evaluate the importance of a coastal embayment area for the generalist predator starfish Astropecten marginatus and Luidia senegalensis , analyzing their spatio-temporal distribution and populational parameters and evaluating whether (1) the species present a differential use of the area, (2) the species use the bay for recruitment, growth and reproduction and (3) there is an ontogenetic or gender related variation in the bay occupation. This study was carried out at Caraguatatuba Bay (SE Brazil), with monthly samples from July/03 to October/04. Although Astropecten was more abundant than Luidia , the two species had similar shifts in abundance, with peaks during cold/dry months, which are partly related to recruitment patterns. Species were distributed mainly towards the southern area of the bay, where A. marginatus had denser aggregations. Both species used the bay for recruitment, growth and reproduction. Males and females of both species occurred in similar numbers (sex ratio 1:1), except in late autumn (May-June) when females became more numerous. An annual reproductive cycle was observed for both species, with spawning occurring mainly in the rainy season, and recruitment mainly during fall/winter. Large individuals (>17 cm) of L. senegalensis were sub-represented in the bay, indicating possible adult migration to deeper areas, whereas A. marginatus had a more resident behavior. Distribution of both species correlated well with diet information previously available, with prey-partitioning suggested as a mechanism that allow their similar occupation of the area, and ontogenetic diet shifts explaining the adult migration of L. senegalensis. This highlights the relevance of feeding information to predict distribution of starfish. Our results elucidate the importance of the studied bay for the life cycle of these keystone species, elucidating species-specific vulnerabilities to coastal degradation and the importance of recognizing populational and distribution parameters in order to inform management policies. [ABSTRACT FROM AUTHOR]

Identifying sources is crucial for proposing effective actions to combat marine litter pollution. Here, we used an innovative approach to identify hotspots of mismanaged plastic waste (MPW) within Brazil and subsequent leakage to the ocean, based on population density, socio-economic conditions, municipal solid waste management and environmental parameters. We estimated plastic waste generation and MPW for each of the 5570 Brazilian municipalities, which totaled 3.44 million metric tons per year. Then, we estimated the probability of litter mobilization and transport (P) and the relative risk of leakage to the ocean (MPW × P). The Guanabara Bay and La Plata River comprised the main oceanic entry hotspots of litter produced in Brazil. The use of national databases allowed us to increase spatial and temporal granularity, offering a detailed baseline for the application of prevention and mitigation actions. However, overcoming data limitations is still a challenge in Brazil as in other Global South countries. [Display omitted] • We estimated mismanaged plastic waste (MPW) and risk of litter leakage to the ocean. • Our innovative risk approach in Brazil considered particularities of the Global South. • Hotspotting differed whether total or per capita MPW was considered. • The main entry points of Brazilian waste to the ocean differed from previous studies. • Understanding sources and pathways of marine litter can improve resource allocation. [ABSTRACT FROM AUTHOR]

Several studies have used the abundance of ghost crabs (Ocypodidae) as an indicator of human impacts on sandy beaches. Such studies have used assessment of burrows, even if the ratio between the number of burrows and crabs might not be consistent across beaches over time. The activity period of crabs frequently mentioned in such studies is always assumed to be during daylight. The few published studies on the daily activity of Ocypode Weber, 1795 preclude generalizations. Our study assessed the activity of O. quadrata Fabricius, 1787 over six 24-hour cycles, using the most affordable filming devices on a restricted-access beach, thus excluding the influence of observers and tourists. The number of individual crabs and the time spent outside the burrows were calculated for every ten minutes of filming. These variables were assessed for correlation to each other, tidal height, temperature, and time of day. Both activity variables were significantly related to tide height, regardless of temperature or time of day. Peaks of activity in O. quadrata occurred during both day and night, and were mostly influenced by circatidal rhythms. [ABSTRACT FROM AUTHOR]

The interconnectedness of ecosystems and the integration of policy and society are relevant aspects of integrated management grounded in knowledge exchange practices. Such processes may also promote social learning, the joint and collaborative knowledge to tackle environmental problems. Thus, understanding knowledge exchange is an additional strategy to promote and understand social learning. This article analyzed a knowledge exchange process related to the elaboration of a proposal for the spatial delimitation of a marine protected area in Brazil, a developing country. By combining process observation and geographical information system tools, proposed areas and criteria for delimitation elaborated by different groups of stakeholders (non-scientists and scientists), separately and in an integrated discussion, were compared and used to test the hypotheses that integration under a knowledge exchange process can bring substantive changes in the outcomes of a management process, and that knowledge exchange processes can promote social learning. Results showed that the integration of different knowledge led to results that none of the groups reached in separate discussions, such as the identification of new areas, delimitation of an area of influence and new criteria for delimitation. Changes in knowledge, the framing and reframing of the processes, understating system complexity and social context were observed, which indicates that knowledge exchange promoted social learning. Additionally, the criteria used to support the delimitation proposals in the studied area can be applied to other marine protected areas in other contexts, and the methods used to guide the discussion can be adapted to other issues. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Oceanography is the property of Instituto Oceanografico da Universidade de Sao Paulo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Butyltin compounds (BTs), including tributyltin (TBT) and its degradation products, dibutyltin and monobutyltin, have been found in a diversity of aquatic systems and causing toxic effects in target and nontarget organisms. They enter in coastal systems through different sources (as antifouling paints, industrial effluents, etc.) where they interact with biotic and abiotic components, and their distribution is commonly determined by the morphological and hydrodynamic conditions of the coastal systems. In this study, we discuss the contamination by BTs on a spatial scale (eight estuaries with three subareas each) and in different compartments of the estuaries (sediments, suspended particulate matter (SPM), and estuarine catfish tissues (liver and gills). Lower concentrations of BTs were found in the sediments (n.d. to 338 ng g) in comparison to studies before a ban of TBT in antifouling paints was enacted, mostly indicating an old input or preservation related with sediment properties and composition. For SPM samples (n.d. to 175 ng L) as well as in fish tissues (n.d. to 1426 ng g), the presence of these compounds was frequent, especially in the fish due to their movement throughout the estuaries and the potential to assess point sources of BTs. These results indicate that BTs persist in the environment, with variation in amounts between investigated estuaries and even at locations inside the same estuary, because of ideal preservation conditions, transport to remote areas, and input from different sources. [ABSTRACT FROM AUTHOR]

The seagrass Halophila decipiens (Ostenfeld) was recently discovered as mono-specific meadows at a number of sites within the São Sebastião Channel (São Paulo State, Brazil). This represents a 60 km extension to the southernmost recorded limit of this genus in the southwest Atlantic and may represent a poleward expansion of this tropical species into temperate seas. Meadows comprised patches of plantlets ranging in diameter from <1 m to >50 m; with paired leaf counts ranging from 150 to 2034/m −2 and estimates of biomass ranging from 8.8– 35.7 g DW m −2 . Across sites, biomass estimates and leaf counts were negatively correlated with depth; while all measured aspects of morphology (i.e. leaf length/width and petiole length) were greater at deeper sites suggesting a possible effect of light limitation. In a subsequent mesocosm experiment testing the physiological effects of SST from the tropics (Bahia state) and warm temperate zone (São Paulo state) H. decipiens returned maximum electron transport rates (ETR max ) after 14 days that were 34% lower when exposed to 20 °C compared to 27 °C (corroborating its tropical affinity), but returned similar effective quantum yields (Δ F / F m ′; 0.695–0.713) attesting to the phenotypic plasticity of the species. Overall we show that the newly discovered populations can tolerate the reduced irradiance and low temperatures of the southwest Atlantic, a trait that may have implications for the broader trend of climate mediated range shifts. [ABSTRACT FROM AUTHOR]

High spatial variability in polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides, such as DDTs, and polybrominated diphenylethers was observed in plastic pellets collected randomly from 41 beaches (15 cities) in 2010 from the coast of state of São Paulo, southeastern Brazil. The highest concentrations ranged, in ng g − 1 , from 192 to 13,708, 3.41 to 7554 and < 0.11 to 840 for PAHs, PCBs and DDTs, respectively. Similar distribution pattern was presented, with lower concentrations on the relatively less urbanized and industrialized southern coast, and the highest values in the central portion of the coastline, which is affected by both waste disposal and large port and industrial complex. Additional samples were collected in this central area and PCB concentrations, in ng g − 1 , were much higher in 2012 (1569 to 10,504) than in 2009/2010 (173 to 309) and 2014 (411), which is likely related to leakages of the PCB commercial mixture. [ABSTRACT FROM AUTHOR]

The population structure, growth and production of the trigonal clam Tivela mactroides were investigated by monthly sampling between January 2003 and October 2004 in two areas (southern and northern) of the intertidal and subtidal zones of Caraguatatuba Bay, Southeastern Brazil. Intertidal sampling was carried out in each area along eight transects perpendicular to the shoreline. In the subtidal zone of both areas, one 50-m dredging was performed along five sampling stations arranged on three transects perpendicular to the coast. The intertidal abundance of T. mactroides was higher in the southern (more dissipative conditions) than in the northern area. High abundances occurred in February- March 2004 in the south and in September 2004 in the north. The size structure showed that younger individuals dominated in the sublittoral, indicating that recruitment occurs in this zone, followed by the migration of these individuals to the intertidal, where they complete their life cycle. Tivela mactroides showed continuous reproduction, with 26 cohorts detected in the study period. The lower estimates for the growth index (ϕ′ = 3.22), mortality rate (Z = 2.10 year−1) and turnover rate (P/B = 1.21 year−1), and conversely the longer life span (2.5 years) of T. mactroides in Caraguatatuba Bay (24°S) compared with Venezuelan populations (10°N) suggests a latitudinal pattern of these life-history traits. The high production of T. mactroides in Caraguatatuba Bay was due to continuous recruitment and rapid and continuous growth, and demonstrates the importance of T. mactroides as a biological resource for many marine species and for the local residents. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Oceanography is the property of Instituto Oceanografico da Universidade de Sao Paulo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The madamango sea catfish, Cathorops spixii (Siluriformes: Ariidae), is often among the most abundant fishes on the South American Atlantic coast. In the present study, conducted in shallow, non-estuarine coastal areas of Caraguatatuba Bight in southeastern Brazil, collections of this species, the most abundant member of the ichthyofauna, included primarily medium-sized individuals, indicating that the area may play a specific role in their development. Although studies of the local ichthyofauna have been much neglected, the area is economically important and its ecological significance is undervalued. This study primarily treats habitat use by C. spixii, assessing certain population parameters and the dietary composition. Monthly samples were taken from August 2003 through October 2004, with three trawls in two areas, corresponding to depths of about 1 to 4 m. The catfish showed two main peaks of abundance in the area, in April/May and July 2004. A mode around 9 cm SL persisted through time, and the entrance of younger recruits peaked from January to April. The low estimate for body-growth parameters (K = 0.16) corroborates some K-strategist characteristics of the species. The asymptotic length was 27.3 cm SL and total mortality (Z) was 1.01 yr−1. Cathorops spixii showed an omnivorous feeding habit, preying mainly upon polychaetes, copepods and bivalves, with considerable seasonality in its diet. [ABSTRACT FROM AUTHOR]

Not only seasonality but also taxonomic resolution of prey categories has been shown to affect diet studies. We analyzed the stomach contents of three sympatric species, Stellifer rastrifer, S. brasiliensis and S. stellifer, sampled monthly from August 2003 to October 2004 in Caraguatatuba Bay, southeastern Brazil. General characteristics and similarities among their diets were evaluated by considering high taxonomic ranks of all prey groups, and also the lower taxonomic ranks of the main prey groups. Dietary similarity was relatively high among species and low between seasons, and both evaluation criteria gave the equivalent results. The rare items, however, provided information about resource partition, and the species compositions of the most important groups were apparently good indicators of food availability. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Oceanography is the property of Instituto Oceanografico da Universidade de Sao Paulo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The somatic and gonad productions of the cirolanid isopod Excirolana armata were analyzed by taking monthly samples from December 2003 to November 2005 on Una beach, São Paulo state (24°S), southeastern Brazil. Sampling was performed along three fixed transects established from the base of the foredunes to the waterline. Weight-specific growth rate was used to estimate the E. armata somatic production for 2004 and 2005, separately. The gonad production was estimated based on the monthly reproductive potential (mean number of eggs/embryos per female × monthly abundance of ovigerous females with near-release broods) for 2004. The annual somatic production of E. armata population varied from 15.57 to 17.25 g AFDW m year and the somatic production/biomass ratio ( P/ B) from 3.55 to 3.14 year for 2004 and 2005, respectively. The P/ B ratios were higher for males (4.02 and 3.19 year for 2004 and 2005) than for females (3.10 year for both years). The annual gonad production ( P = 1.07 g AFDW m year) contributed about 15 and 6% to the total production ( P + P) of females and the population, respectively. The proportion of gonad to somatic production of females ( P/ P) increased with individual size (ca 90% in the 7.5 mm size class), and the annual weight-specific gonad production ( P/ B ratio) was estimated to 0.24 year. The high P/ B ratios estimated for E. armata derive from the fast growth of individuals and show the importance of this population to the energy flow on Una beach ecosystem. However, the low percentage of juveniles verified in this population and in other studies of populations of the genus Excirolana is discussed as an important source of underestimation of P/ B ratio. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Oceanography is the property of Instituto Oceanografico da Universidade de Sao Paulo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Oceanography is the property of Instituto Oceanografico da Universidade de Sao Paulo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Portunid crabs are an important resource in estuaries, and require appropriate management to guarantee their long-term availability. We investigated the population dynamics and reproduction of Callinectes danae in the Estuarine–Bay Complex of São Vicente, São Paulo, Brazil, to provide basic biological information for public policies for the management of this fishery. Monthly samples were obtained from March 2007 to February 2008 on eight transects, four in the estuary and four in the bay. A total of 2261 specimens (403 males, 1288 females, of which 570 were ovigerous) were collected. Males were significantly larger than females, and the size–frequency distribution was unimodal for males, females and ovigerous females. The sex ratio was nearly always skewed toward females (M:F - 1:4.6). C. danae showed seasonal-continuous reproduction, with high reproductive activity in the warmer season. C. danae breeds in the estuarine–bay complex, with males and juvenile females concentrated in the estuary. After copulation, fertilized females migrate to the estuary entrance and the bay, where ovigerous females are commonly found spawning in high-salinity areas. Therefore, to manage this important economic resource, both the estuary and the bay should be considered for protection, but special attention should be given to the estuary entrance during the summer months, when ovigerous females concentrate. [ABSTRACT FROM AUTHOR]

Biological invasions are a present and growing environmental problem because non-indigenous organisms may affect the structure and functioning of native communities. In the marine environment there are records of invasive species in almost all phyla, including crustaceans, and the portunid crabs of the genus Charybdis are among the most widespread invasive groups. We report the first record of Charybdis variegata (Fabricius, 1798) from the western Atlantic coast. This species was collected on an intertidal rocky shore near Santos Harbor, São Paulo state, Brazil. Of 311 portunid crabs sampled, 309 individuals belonged to the non-indigenous Charybdis hellerü (A. Milne Edwards, 1867), one was a native Cronius ruber (Lamarck, 1818), and one was identified as the non-indigenous Charybdis variegata. This individual was a juvenile female measuring 27.5 mm in carapace width. The taxonomic traits used for species identification, as well as a morphological comparison between C. hellerü and C. variegata are presented. The introduction route and establishment status of this species are also discussed. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Integrated Coastal Zone Management / Revista de Gestão Costeira Integrada is the property of Associacao Portuguesa dos Recursos Hidricos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The influence of short-term (daily) variation in environmental conditions (rainfall, wind, tide, river flow) on debris accumulation was examined on two beaches at an estuarine outlet. Sampling occurred over 60 consecutive days along two sections (Internal Area, IA; and External Area, EA) of the Paranaguá Estuary Complex's southern outlet, in Paraná, southern Brazil. The IA is sheltered from direct wave action, whereas the EA is more exposed to wave and wind action from the open ocean. The IA accounted for 71% of the total debris, while the EA accounted for 29%. Debris abundance was highest after intermediate bouts of rainfall, although river flow only affected debris accumulation in the IA. Wind and tide influenced accumulation differently across sites. These results highlight the importance of short-term variation in the accumulation of marine debris on sandy beaches, which should be considered when designing and monitoring assessment programs and removal strategies. • Environmental conditions influence debris accumulation patterns on beaches at an estuarine outlet. • The effects of short-term variation on beach-stranded debris may be dependent on beach location. • Domestic plastic is the most common type of debris found in estuarine and oceanic beaches. • Small-scale temporal studies are important in quantifying marine debris dynamics. [ABSTRACT FROM AUTHOR]

Beach clam fisheries often provide an alternate income for traditional fishermen, but this activity is highly vulnerable to urbanization of coastal areas. Tivela mactroides is a beach clam commonly harvested in the Caribbean (Venezuela) and on the south-eastern Brazilian coast. Only localized records on its spatial structure in size and abundance are available to support management of this clam. The present study showed that the spatial distribution in abundance and size of T. mactroides in Caraguatatuba Bay, state of São Paulo, Brazil, has both along- and across-shore (intertidal and subtidal) components. The nature of this distribution should be taken into account in the design of further population or monitoring studies concerning this species. Clam density varied along-shore, with a tendency towards higher numbers of individuals in the stations near the northern side of river mouths of this bay. Lower densities were related to the occurrence of sea-stars and sand-dollars. The intertidal and subtidal across-shore distribution of clam abundance and size varied between and within areas (southern and northern). The individuals from the southern area were concentrated at intermediate tidal levels (0.2-0.6 m in relation to mean low water), whereas in the northern area the clams were more homogeneously distributed. The uppermost limit of their distribution was 0.8 m (southern) and 0.4 m (northern), and an upwards tendency towards increased size was more evident in the northern area. In the subtidal, abundance and individual size tended to increase from the deepest (4.5 m) to the shallowest (0.5 m) levels only in the southern area. Individual clams in the northern area tended to be smaller and more abundant than in the southern area. The species had an ontogenic distribution: small-sized individuals were recorded only in the subtidal. Possible causes for these patterns and for the differences between areas (human exploitation, organic pollution, beach morphodynamics, differential recruitment, and adult-larvae interactions) are discussed, and specific studies are suggested to evaluate formally the proposed hypotheses. [ABSTRACT FROM AUTHOR]

Increased rainfall has become a key threat in recent decades for subtropical coastal regions. On sandy beaches that are associated with streams and rivers, the intensification of freshwater inputs is expected to reduce the salinity of interstitial waters and affect benthic biodiversity. Large freshwater gradients are promoted by river mouths and also change beach morphodynamic and sediment organic contents, which are covariates that have hindered the understanding of salinity-specific effects on benthic species in previous studies. Here, we aimed to assess how salinity reduction affects macrobenthic communities at small spatial scales to control the effects of environmental covariates. We assessed the macrofaunal spatial changes across few-meters gradients of freshwater influence (30 m) that were promoted by small streams (~2 m wide) within three subtropical beaches in southeastern Brazil. Our results showed that salinity was the only environmental factor that explained the macrofaunal variations across such small-scale gradients. We noted that salinity reductions decrease the overall macrobenthic abundance and richness in the first 15 m close to streams. Such variations are associated with changes in polychaete abundance (mainly Scolelepis squamata), which form larger patches with 1200–2800 individuals/m2 only at sites with high salinity (greater than 25). We also found that a salinity reduction from 33 to 20 may promote a decrease of 85% in polychaete abundance near the streams. Nevertheless, salinity reductions did not affect crustacea abundance across the gradient. In the current global change context, these results suggest that freshwater input has great potential to impact polychaete patches, reduce macrobenthic biomass and secondary production and thus threaten important beach functions and services, such as bioturbation and food provision for the top predators. • Increased freshwater input on beaches reduce salinity and can threat benthic fauna. • We assessed the macrofaunal changes across small-scale gradients of salinity. • We find that salinity reduction decreases macrobenthic abundance and richness. • Polychaetes form large patches of abundance only under salinities greater than 25. • Freshwater inputs can impact benthic biomass production on sandy beaches. [ABSTRACT FROM AUTHOR]

While coastal management has been recognized as an urgent and strategic process since 1970s worldwide, it is still struggling to show robust outcomes in some countries and even among regions within countries. Coastal Ecological and Economic Zoning was proposed in 1988 as an integrated environmental and territorial management tool by the Brazilian National Coastal Management Plan (NCMP). This paper applied a recently-developed methodological framework towards the analysis of C-EEZ implementation processes in the context of the 17 coastal States in Brazil. The results evidence particularities that may improve coastal management policies and highlights the situation of late consolidation of this management tool, with evident asymmetries along the Brazilian coast. Although the C-EEZ is one of the most enduring initiatives in coastal management in Brazil, some critical issues still need to be solved, such as articulation among sectors of society, generation of technical products for society, provision of State's annual budget laws, integration with land territorial management policies, identification and mitigation of conflicts throughout the territory and its uses, foster public participation, integration between the technical teams and public spheres, and guidance on environmental licensing processes by the states. Finally, it is proposed that the discussion be brought to the social actors involved with the coastal management theme, seeking to optimized efforts and financial, material and human resources, aiming for greater effectiveness of what really matters: the sustainable development of the coastal zone in Brazil. [Display omitted] • There is a gap in the methods and assessments of coastal zoning implementation worldwide. • A set of 35 indicators to analyse the Coastal Ecological and Economic Zoning in Brazil was developed and applied. • Different degrees in implementation success were recorded among the 17 Brazilian coastal states • The results evidenced local particularities that can improve coastal zoning policies implementation. • Proposals for a better coastal zoning performance were suggested. [ABSTRACT FROM AUTHOR]

This paper analyses the perception of Brazilian high-level ocean-related governmental authorities in charge of steering future pathways for the national ocean economy. We adapted and applied a model for evaluating sustainability transition experiments to visualize what ought to be the ingredients of an experimental agenda focused in advancing the country's marine spatial planning (MSP) as a fundamental instrument for achieving a shared Vision of blue economy for Brazil. Our results point that such a vision does not currently exist to guide the ocean governance system, raising attention for potential gaps in the consideration of environmental sustainability and social equity that needs to be addressed when shaping one. We discuss what ought to be the core ingredients of a national-level transition experiment for advancing MSP in Brazil (inputs, processes, outcomes and results). The adoption of a network-based MSP transition experiment in Brazil, from an initial technically-oriented to a subsequent process-oriented approach, may improve the sociopolitical arena's functional ocean governability, by (1) promoting a process-framework for improving the overall presence and quality of area-based governance-related knowledge-exchange; (2) supporting the policy-innovators quest for integrated governance through imagination and rationalization of appropriate institutional changes; (3) providing space for streamlining disparate governance responses into co-evolutionary pathways; (4) measuring improvements in the performance of innovative governance attempts; and (5) allowing for involved parties to confront asymmetric power relations in the shaping of a more environmentally sustainable and socially equitable ocean economy. • Marine spatial planning is instrumental to ocean sustainable development. • Brazil has no cohesive, well-formulated vision for a blue economy agenda. • Actual technically-oriented MSP in Brazil limits functional ocean governability. • Inter-network area-based activities can foster an environmentally sustainable and socially equitable pathway. • Five ocean governability potentials of sustainability experiments are provided. [ABSTRACT FROM AUTHOR]

A novel blue planning discourse has been elevated through marine spatial planning (MSP) discussions in Brazil since 2011, following the evolution of international ocean governance policy innovation in the past decades. This paper investigates the early evolution stages of a socio-political arena around MSP in Brazil using as reference the IOC-UNESCO's step-by-step approach. It also employs the interactive governance theory to describe and analyze the challenges and opportunities in four phases in the evolution of a MSP policy arena at the Brazil's Blue Amazon level; and discuss it in terms of five major functional governability narratives this trajectory evoke to actors in this new interactive governance playing field. The evolution of Brazilian MSP arena was triggered by discussions at the international level (Phase I – 2011 to 2012), which encountered some resistance until it was reframed under a new formal intra-governmental institutional building process (Phase II – 2012 to 2013). Following a rapid surge and apparent early advances in MSP discussions (Phase III - 2014), the final (current) Phase IV can be characterized by the quiescence of the innovation process led by federal government, and the rise in numbers and diversity of agents in the MSP policy arena. It is noted with this analysis that Brazil is behind the international schedule on MSP, as it is still struggling in the 'articulation and framing phase'. The analysis of thirty-four challenges and opportunities identified in this trajectory shows that improving functional capacities to govern (governability) the ocean in Brazil will require all actors to: (1) streamline cross-network knowledge-exchange to improve the nascent MSP arena; (2) further understand institutional dynamics impeding policy integration; (3) foster a more symmetrically responsive ocean governance arena; (4) promote coordinated scaling through principle-based policy-building and; (5) strengthening critical but proactive civil society participation at multiple, interrelated area-based ocean governance innovation frontlines. The accumulated capacities shared by existing knowledge-to-action networks in Brazil may render the emerging arena a dynamic, creative, and regional ocean learning experiment. • Four phases in the early evolution of a MSP arena in Brazil are identified • The Brazilian arena remains in an early articulation and framing phase • Subnational experiences are accessible to inspire coevolution of the national arena • Challenges and opportunities call for improved ocean governance capacities • Five functional governability narratives are distilled with associated solutions [ABSTRACT FROM AUTHOR]

Abstract Microplastics are important vectors for the transport and accumulation of persistent organic contaminants in coastal and marine environments. We determined the concentration of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) associated with microplastic pellets collected along a 39-km stretch of Brazil's South Atlantic coastline to understand the spatial dynamics and potential risk posed by these contaminants. Total PAH concentrations ranged from 1,454 to 6,002 ng g−1 and regularly exceeded the threshold effect level (TEL) for sediments defined by the United States Environmental Protection Agency. Sampling stations, spaced evenly along the coastline (i.e., 3-km intervals) exhibited a general north-to-south decline in the concentrations of some PAHs, but this spatial gradient was complicated by small-scale differences in the concentrations and composition of associated contaminants. Similarly, analysis of individual isomer ratios revealed further complexity driven by differences in the contribution of petrogenic versus pyrolytic inputs which pose different levels of risk to marine organisms. PCB concentrations ranged from 0.8 to 104.6 ng g−1 and were dominated by low chlorinated congeners likely to have originated from major industrial areas to the north. Overall, this study highlights the challenge of directly linking microplastic pollution with the potential toxicological effects of organic contaminants in coastal waters. We recommend that monitoring programs should explicitly consider both the origin (i.e., pellet sources and dispersal pathways) and nature of organic contamination (i.e., concentration and composition) when assessing the risks for biota and human health. Highlights • Microplastics are vectors for the transport of organic pollutants in marine waters. • We tested the PAH & PCB concentrations of pellets collected along an open coastline. • ΣPAHs regularly exceeded the threshold effect level for marine sediments. • PCBs varied widely and were dominated by low-CL congeners implying distal sources. • Risk assessments may benefit by considering both source & contaminant concentration. [ABSTRACT FROM AUTHOR]

Pomadasys corvinaeformis inhabits sandy and rocky bottoms in coastal waters, and is common in trawl samples taken from beaches. The species is very abundant on the Brazilian coast, and is of high economic and ecological importance. This study examined the spatio-temporal distribution, population biology and diet of P. corvinaeformis in Southeastern Brazil. Samples were taken by trawling monthly from August 2003 to October 2004, in two previously selected areas. The Northern area is more exposed to wave activity and is influenced by a river, functioning as a small estuary. In contrast, the Southern area is relatively sheltered from wave energy and influenced to a lesser degree by smaller rivers. The length of the specimens was measured, and the sex and gonadal stage were macroscopically identified. The abundance of this species was compared between areas and among months. The diet was analyzed seasonally by the frequency of occurrence, the percent volume, and the index of alimentary importance. P. corvinaeformis occurred in unequal proportions in the two study areas (86% in the Northern area and 14% in the Southern area) and was found most abundant in May 2004, followed by June 2004. The proportion of mature and in-maturation individuals increased gradually from autumn to summer. Nine major groups of food items were recorded in the diet of P. corvinaeformis, and crustaceans comprised five of the categories: unidentified crustacean fragments, zoea larvae, amphipods, copepods and shrimps. In both, fish stomach and intestine, crustacean fragments were the most frequent item. The second most frequent items were shrimp in the stomach, and amphipods in the intestine (mainly represented by their tubes). These results demonstrate that P. corvinaeformis can be considered a carnivore, with a preference on benthic organisms. [ABSTRACT FROM AUTHOR]

A persistent challenge to managing coastal wetlands in a way that will mitigate climate impacts is understanding how soil organic carbon (Corg) stocks change over spatial and temporal scales. This study tested how seasonal change in riverine flows and soil biogeochemical attributes (grain-size, degree of wave disturbance and microphytobenthic productivity) can influence the Corg stock estimates of an unvegetated tidal flat within a Brazilian subtropical bay. We used a Generalized Additive Modelling (GAM) approach to accurately predict and map subtle changes in the Corg pools of these expansive, but often overlooked coastal ecosystems. The most important predictors across seasons were sediment grain-size and wave exposure. Seasonally important covariates were riverine flow and microphytobenthic productivity (during the warm and wet summer season). We then compared the high-resolution map outputs derived from models with more traditional approaches (interpolation and extrapolation) to see how these different methods might influence estimates of the carbon stocks for the entire bay (i.e., an area covering 115 ha). Modelled estimates for the bay (1945 ± 45 Mg Corg) where more conservative and had lower associated error than interpolated (2196 ± 185 Mg) and extrapolated estimates (2535 ± 117 Mg). Given the current urgency to understand the carbon sequestration potential of coastal ecosystems, the present findings are important and draw attention to the often overlooked, but important carbon pools of intertidal mudflats. • Measuring soil organic carbon (Corg) stocks is a challenge in coastal environments. • We tested if seasonally variable covariates can help predict Corg pools of mudflats. • Important factors were soil grain-size, waves, river flow & benthic productivity. • Modelled Corg estimates were lower and more accurate than other approaches. • We highlight the variability of carbon pools from unvegetated coastal habitats. [ABSTRACT FROM AUTHOR]

Classification of beaches into morphodynamic states is a common approach in sandy beach studies, due to the influence of natural variables in ecological patterns and processes. The use of remote sensing for identifying beach type and monitoring changes has been commonly applied through multiple methods, which often involve expensive equipment and software processing of images. A previous study on the South African Coast developed a method to classify beaches using conditional tree inferences, based on beach morphological features estimated from public available satellite images, without the need for remote sensing processing, which allowed for a large-scale characterization. However, since the validation of this method has not been tested in other regions, its potential uses as a trans-scalar tool or dependence from local calibrations has not been evaluated. Here, we tested the validity of this method using a 200-km stretch of the Brazilian coast, encompassing a wide gradient of morphodynamic conditions. We also compared this locally derived model with the results that would be generated using the cut-off values established in the previous study. To this end, 87 beach sites were remotely assessed using an accessible software (i.e., Google Earth) and sampled for an in-situ environmental characterization and beach type classification. These sites were used to derive the predictive model of beach morphodynamics from the remotely assessed metrics, using conditional inference trees. An additional 77 beach sites, with a previously known morphodynamic type, were also remotely evaluated to test the model accuracy. Intertidal width and exposure degree were the only variables selected in the model to classify beach type, with an accuracy higher than 90% through different metrics of model validation. The only limitation was the inability in separating beach types in the reflective end of the morphodynamic continuum. Our results corroborated the usefulness of this method, highlighting the importance of a locally developed model, which substantially increased the accuracy. Although the use of more sophisticated remote sensing approaches should be preferred to assess coastal dynamics or detailed morphodynamic features (e.g., nearshore bars), the method used here provides an accessible and accurate approach to classify beach into major states at large spatial scales. As beach type can be used as a surrogate for biodiversity, environmental sensitivity and touristic preferences, the method may aid management in the identification of priority areas for conservation., Competing Interests: Guilherme N. Corte is an Academic Editor for PeerJ. The other authors declare that they have no competing interests., (©2022 Checon et al.)

The influence of three meteorological/oceanographic conditions - frontal systems (FS), high riverine discharges (HRD) and regular weather conditions (RWC) - over the quantity (Overall Abundance and Richness of types) and quality (composition and most probable source) of marine debris was assessed in sand beaches along three sectors (internal, I; median, M; and external, E) of an estuarine gradient. The highest overall abundance and richness of types were observed in HRD (I and E), while the lowest were observed in RWC (I and M). The external sector showed lowest abundance in FS. Greatest numbers of "domestic" and "sewage related debris" were observed under HRD (I > E > M). Greatest numbers of "fisheries" items were observed in HRD (I and E). For "unknown" sourced items, there was no indication of a single condition with smaller quantities (E > I = M). Results suggest that adopting oceanographical and meteorological conditions for analysis have the potential to detect temporal variations., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Multiple simultaneous stressors induced by anthropogenic activities may amplify their impacts on marine organisms. The effects of ocean acidification, in combination with other anthropogenic impacts (apart from temperature) are poorly understood, especially in coastal regions. In these areas, shading caused by infrastructure development, such as harbor construction, may potentially interact with CO 2 -induced pH reduction and affect invertebrate populations. Here, we evaluated the effects of reduced pH (7.6) and shading (24h in darkness) on mortality, growth, calcification and displacement behavior to live predator (danger signal) and dead gastropod (resource availability signal) odors using juveniles of the hermit crab Pagurus criniticornis collected in Araçá Bay (São Paulo state, Southeastern Brazil). After a 98 day experimental period, both stressors had a significant interaction effect on mortality, and an additive effect on total growth. No difference in calcification was recorded among treatments, indicating that individuals were able to maintain calcification under reduced pH conditions. When exposed to odor of live predators, crab responses were only affected by shading. However, an interactive effect between both stressors was observed in response to gastropod odor, leading to reduced displacement behavior. This study shows how local disturbance impacts may enhance the effects of global environmental change on intertidal crustacean populations., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Stranding combined with mass-mortality events of sandy-beach organisms is a frequent but little-understood phenomenon, which is generally studied based on discrete episodes. The frequency, magnitude, and possible causes of stranding and mass-mortality events of the trigonal clam Tivela mactroides were assessed based on censuses of stranded individuals, every four days from September 2007 through December 2008, in Caraguatatuba Bay, southeastern Brazil. Stranded clams were classified as dying (closed valves did not open when forced) or dead (closed valves were easily opened). Information on wave parameters and the living intertidal clam population was used to assess possible causes of stranding. This fine-scale monitoring showed that stranding occurred widely along the shore and year-round, with peaks interspersed with periods of low or no mortality. Dead clams showed higher mean density than dying individuals, but a lower mean shell length, attributed to a higher tolerance to desiccation of larger individuals. Wave height had a significant negative relationship to the density of dying individuals, presumed to be due to the accretive nature of low-energy waves: when digging out, clams would be more prone to be carried upward and unable to return; while larger waves, breaking farther from the beach and with a stronger backwash, would prevent stranding in the uppermost areas. This ecological finding highlights the need for refined temporal studies on mortality events, in order to understand them more clearly. Last, the similar size structure of stranded clams and the living population indicated that the stranded individuals are from the intertidal or shallow subtidal zone, and reinforces the ecological and behavioral components of this process, which have important ecological and socioeconomic implications for the management of this population.

Tributyltin (TBT) contamination is still recorded in the environment even after its ban in antifouling paints. Since most biomonitors of TBT contamination, through imposex evaluation, are hard-bottom gastropods, the identification of soft-bottom sentinels has become useful for regions where rocky shores and coral reefs are absent. Thus, an evaluation of Olivella minuta and Hastula cinerea as monitors of TBT contamination was performed in two sandy beaches located under influence area of São Sebastião harbor (São Paulo state, Brazil), where previous and simultaneous studies have reported environmental contamination by TBT. In addition, the imposex occurrence in H. cinerea was assessed in an area with low marine traffic (Una beach), also located in São Paulo State. A moderate imposex incidence in O. minuta was detected in Pernambuco (% I = 9.36, RPLI = 4.49 and RPLIstand = 4.27) and Barequeçaba (% I = 2.42, RPLI = 0.36 and RPLIstand = 0.81) beaches, indicating TBT contamination. In contrast, more severe levels of imposex were recorded for H. cinerea in Una beach (% I = 12.45) and mainly in Barequeçaba beach (% I = 98.92, RPLI = 26.65). Our results suggest that O. minuta and H. cinerea have good potential as biomonitors for TBT based on their wide geographical distribution, common occurrence in different coastal sediment habitats, easy collection, and association with TBT-contaminated sediments.

A marine biological invasion is a natural process accelerated by human activities, and the crab Charybdis hellerii is an example of a globally widespread invasive species. This study evaluated color variation in C. hellerii and its relationship to the sex, size and sexual maturity of these crabs, and compared the efficiency of a freeware digital image-editing program with a commercially available program. The color of the individuals was analyzed using standardized digital images. The color pattern varied significantly with size; smaller and immature individuals were darker than larger and mature ones. The female abdomen changed in morphology and color with sexual maturity, becoming wider and orange-colored. There was no statistical difference in the color values between males and females and immature males did not show morphological or color differences in their abdomen. This study highlights the possible relationships of the color and physiological state of the reproductive system, which could help in future studies of behavior, avoiding the need to dissect and/or remove individuals from nature for assessment of sexual maturity. The freeware program showed the same efficiency in digital image analysis as a widely known commercial program.

The madamango sea catfish, Cathorops spixii (Siluriformes: Ariidae), is often among the most abundant fishes on the South American Atlantic coast. In the present study, conducted in shallow, non-estuarine coastal areas of Caraguatatuba Bight in southeastern Brazil, collections of this species, the most abundant member of the ichthyofauna, included primarily medium-sized individuals, indicating that the area may play a specific role in their development. Although studies of the local ichthyofauna have been much neglected, the area is economically important and its ecological significance is undervalued. This study primarily treats habitat use by C. spixii, assessing certain population parameters and the dietary composition. Monthly samples were taken from August 2003 through October 2004, with three trawls in two areas, corresponding to depths of about 1 to 4 m. The catfish showed two main peaks of abundance in the area, in April/May and July 2004. A mode around 9 cm SL persisted through time, and the entrance of younger recruits peaked from January to April. The low estimate for body-growth parameters (K = 0.16) corroborates some K-strategist characteristics of the species. The asymptotic length was 27.3 cm SL and total mortality (Z) was 1.01 yr(-1). Cathorops spixii showed an omnivorous feeding habit, preying mainly upon polychaetes, copepods and bivalves, with considerable seasonality in its diet.