Linking Habitat and Associated Abiotic Conditions to Predict Fish Hotspots Distribution Areas within La Paz Bay: Evaluating Marine Conservation Areas

Hotspots are priority marine or terrestrial areas with high biodiversity where delineation is essential for conservation, but equally important is their linkage to the environmental policies of the overall region. In this study, fish diversity presences were linked to abiotic conditions and different habitat types to reveal multi-species and hotspots models predicted by ecological niche modelling methods within the Bay of La Paz, Mexico (south of Gulf of California). The abiotically suitable areas for 217 fish species were identified based on historical (1975–2020) presence data sets and a set of environmental layers related to distances from mangroves and rocky shores habitats, marine substrate, and bottom geomorphology conditions. Hotspot model distribution was delineated from a multi-species model identifying areas with ≥60 species per hectare and was compared to the marine conservation areas such Balandra Protected Natural Area (BPNA), illustrating how these models can be applied to improve the local regulatory framework. The results indicate that (1) there is a need for the BPNA to be enlarged to capture more of the delineated hotspot areas, and thus an update to the management plan will be required, (2) new conservation areas either adjacent or outside of the established BPNA should be established, or (3) Ramsar sites or other priority areas should be subject to legal recognition and a management plan decreed so that these vital habitats and fish diversity can be better protected.

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Reduced fish diversity despite increased fish biomass in a Gulf of California Marine Protected Area

PeerJ ◽

10.7717/peerj.8885 ◽

2020 ◽

Vol 8 ◽

pp. e8885

Author(s):

Georgina Ramírez-Ortiz ◽

Héctor Reyes-Bonilla ◽

Eduardo F. Balart ◽

Damien Olivier ◽

Leonardo Huato-Soberanis ◽

...

Keyword(s):

Gulf Of California ◽

Fish Assemblages ◽

Marine Protected Area ◽

Marine Conservation ◽

Primary Objective ◽

Fish Diversity ◽

Fishing Pressure ◽

General Increase ◽

Functional Richness ◽

Density And Biomass

Multi-use marine protected areas (MUMPAs) are a commonly applied tool for marine conservation in developing countries, particularly where large no-take reserves are not socially or politically feasible. Although MUMPAs have produced benefits around the world, the persistence of moderate fishing pressure reduces the likelihood of achieving the primary objective of these areas, which is the conservation of ecosystems. In this study we used traditional and functional metrics to evaluate how fish assemblages changed through time in a MUMPA, including shifts in species responses and in ecological processes. We conducted visual censuses of fishes at Espíritu Santo Island, México (MUMPA; N = 320; 24°N, 110°W) from 2005 to 2017 to assess fish richness, size-distribution and density. Three functional indices were calculated using six traits (size, mobility, period of activity, aggregation, position in water column and diet): functional richness (volume occupied by species), dispersion (complementarity between species) and originality (inverse of functional redundancy). We compared fish diversity among three management zone types (sustainable fishing, traditional fishing and no-take zones), through a 13-year period, assessing which species increased or decreased in occurrence, density, and biomass, and how indices respond over time. Despite a general increase in biomass and stability in density and originality, we detected a reduction in fish biodiversity in the form of declines in species and functional richness, which could imply the risk of local extinction and decrease in certain ecosystem processes. In addition, changes in functional dispersion showed that some functions are losing representation through time. Although no single cause is apparent, such factors as competitive interactions, habitat loss and persistence of fishing pressure potentially explain these decreases. The rise in biomass was associated with a general increase in the average size, rather than increased biomass of commercial species, as the latter remained stable during the study period. Expansion of no-take areas, enforcement of fishing regulations, and surveillance in core zones, should be implemented to reverse the decline in particular species and to promote conservation of fish functional diversity in this MUMPA.

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The role of rarity as a surrogate of marine fish species representation

PeerJ ◽

10.7717/peerj.8373 ◽

2020 ◽

Vol 8 ◽

pp. e8373

Author(s):

Fabio Albuquerque ◽

Yaiyr Astudillo-Scalia

Keyword(s):

Species Richness ◽

Marine Conservation ◽

Marine Biodiversity ◽

Fish Diversity ◽

Area Network ◽

Number Of Species ◽

Fish Biodiversity ◽

Presence Data ◽

Species Rarity ◽

A Site

Because the distribution of most of the species is poorly known, conservationists use surrogates to help maximize the representation level of all species. Historically, species richness has been used to calculate the importance of priority areas for conservation, but several studies revealed sites with high species richness often fail to determine the smallest number of sites that will protect the highest number of species. Rarity, however, has played a prominent role in safeguarding planning units. While the performance of rarity has been previously assessed in terrestrial systems, we tested the hypothesis that rarity of a site can be used as a measure of the importance of a site to a conservation network in marine ecosystems. We used the presence data (at a 1-degree resolution) to calculate five rarity indices of fish diversity at a global extent and compared the results to those obtained by using species richness and site complementarity. Our objectives were to: (1) determine if rarity indices can be used as surrogates of fish biodiversity by representing the highest number of species in the smallest number of sites; and (2) determine if the effectiveness of these indices to represent fish biodiversity is impacted by the metric used to define rarity. Results indicate that rarity could be an effective surrogate for marine fishes, as most results showed a mean of 100% effectiveness. In the context of marine biodiversity conservation, results show that rarity indices could be considered affordable and feasible surrogates of species representation, with the most significant benefit to those areas of the world that are in most need to access alternative tools. Results also open a new area of collaboration between biogeography and marine conservation biology since planners can use biogeographical patterns of rarity to enhance the performance of the current protected area network.

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Variation in isotopic trophic structure and fish diversity in mangrove systems subject to different levels of habitat modification in the Gulf of California, Mexico

Bulletin of Marine Science ◽

10.5343/bms.2015.1100 ◽

2016 ◽

Vol 92 (4) ◽

pp. 399-422 ◽

Cited By ~ 4

Author(s):

Francisco J López-Rasgado ◽

Salvador E Lluch-Cota ◽

Eduardo F Balart ◽

Sharon Z Herzka

Keyword(s):

Gulf Of California ◽

Trophic Structure ◽

Habitat Modification ◽

Fish Diversity ◽

Different Levels

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Supporting Spatial Management of Data-Poor, Small-Scale Fisheries With a Bayesian Approach

Frontiers in Marine Science ◽

10.3389/fmars.2021.621961 ◽

2021 ◽

Vol 8 ◽

Author(s):

Jennifer Rehren ◽

Maria Grazia Pennino ◽

Marta Coll ◽

Narriman Jiddawi ◽

Christopher Muhando

Keyword(s):

Spatial Distribution ◽

Marine Conservation ◽

Environmental Drivers ◽

Small Scale ◽

Target Species ◽

Short Term ◽

Conservation Areas ◽

Bayesian Hierarchical ◽

Small Scale Fisheries ◽

Spatial Management

Marine conservation areas are an important tool for the sustainable management of multispecies, small-scale fisheries. Effective spatial management requires a proper understanding of the spatial distribution of target species and the identification of its environmental drivers. Small-scale fisheries, however, often face scarcity and low-quality of data. In these situations, approaches for the prioritization of conservation areas need to deal with scattered, biased, and short-term information and ideally should quantify data- and model-specific uncertainties for a better understanding of the risks related to management interventions. We used a Bayesian hierarchical species distribution modeling approach on annual landing data of the heavily exploited, small-scale, and data-poor fishery of Chwaka Bay (Zanzibar) in the Western Indian Ocean to understand the distribution of the key target species and identify potential areas for conservation. Few commonalities were found in the set of important habitat and environmental drivers among species, but temperature, depth, and seagrass cover affected the spatial distribution of three of the six analyzed species. A comparison of our results with information from ecological studies suggests that our approach predicts the distribution of the analyzed species reasonably well. Furthermore, the two main common areas of high relative abundance identified in our study have been previously suggested by the local fisher as important areas for spatial conservation. By using short-term, catch per unit of effort data in a Bayesian hierarchical framework, we quantify the associated uncertainties while accounting for spatial dependencies. More importantly, the use of accessible and interpretable tools, such as the here created spatial maps, can frame a better understanding of spatio-temporal management for local fishers. Our approach, thus, supports the operability of spatial management in small-scale fisheries suffering from a general lack of long-term fisheries information and fisheries independent data.

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PEMANFAATAN DAN PENGELOLAAN KAWASAN KONSERVASI LAUT DAERAH GILI SULAT DAN GILI LAWANG

Jurnal Sosial Ekonomi Kelautan dan Perikanan ◽

10.15578/jsekp.v5i2.5796 ◽

2017 ◽

Vol 5 (2) ◽

pp. 129

Author(s):

Hakim Miftakhul Huda ◽

Yesi Dewita Sari

Keyword(s):

Economic Valuation ◽

Management Strategies ◽

Secondary Data ◽

Marine Conservation ◽

Conservation Areas ◽

Current Management ◽

Indirect Benefits ◽

Fish Resources ◽

Annual Total ◽

Direct And Indirect Benefits

Tingginya intensitas aktivitas penangkapan ikan telah menyebabkan degradasi sumber daya ikan pada beberapa daerah penangkapan ikan. Salah satu langkah untuk menjaga keberlanjutan dan meminimalkan degradasi sumber daya ikan adalah membentuk kawasan konservasi laut daerah. Penelitian ini bertujuan untuk mengetahui pemanfaatan dan pengelolaan Kawasan Konservasi Laut Daerah (KKLD) Gili Sulat-Gili Lawang, Provinsi Nusa Tenggara Barat. Penelitian menggunakan metode valuasi ekonomi sumber daya untuk menganalisis gabungan data primer dan sekunder. Hasil penelitian menunjukkan total nilai manfaat KKLD Gili Sulat-Gili Lawang adalah Rp 8,99 milyar per tahun yang meliputi manfaat langsung dan tidak langsung. Hasil penelitian menunjukan pengelolaan terhadap KKLD ditinjau dari biaya, aktor atau pelaku dan aktivitas pengelolaan sampai saat ini belum optimal. Penelitian ini menyarankan perlunya menyusun strategi pengelolaan yang tepat untuk mengoptimalkan maksud dan tujuan dibentuknya KKLD. Tittle: Utilization and Management of The Gili Sulat and The Gili Lawang Regional Marine Conservation Area.Highly intensive of fishing activities lead to degradation of fish resources in some fishing grounds. One effort to maintain sustainability of fish resources and minimize its degradation is to establish local marine conservation areas. This study aims to analyze utilization and management of Gili Sulat-Gili Lawang local marine conservation areas (or locally known as KKLD) in Wes Nusa Tenggara Province. This study applies economic valuation methods to analyze combination of primary and secondary data. Results of this study show that annual total benefit values of Gili Sulat-Gili Gili Lawang KKLD is IDR 8,99 billion which includes direct and indirect benefits. In terms of costs, actors and management activities, current management of KKLD is less optimal. Therefore, this study recommends to develop appropriate management strategies to optimize the purposes of KKLD establishment.

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A MULTI-SPECIES MICROALGAE BLOOM IN BAHIA DE LA PAZ, GULF OF CALIFORNIA, MEXICO (JUNE 2008)

CICIMAR Oceánides ◽

10.37543/oceanides.v24i1.50 ◽

2009 ◽

Vol 24 (1) ◽

pp. 15 ◽

Cited By ~ 1

Author(s):

I. Gárate-Lizárraga ◽

C. J. Band-Schmidt ◽

F. Aguirre-Bahena ◽

T. Grayeb del Alamo

Keyword(s):

Phytoplankton Biomass ◽

Gulf Of California ◽

Phytoplankton Community ◽

Red Tide ◽

Total Density ◽

La Paz ◽

Gyrodinium Instriatum ◽

High Species Richness ◽

Myrionecta Rubra ◽

Ecological Importance

Red tide patches were observed in Bahía de La Paz in June 17 and 18 of 2008. According to temperature and wind data this bloom occurred under upwelling-like conditions. Examination of the red tide samples showed the ciliate Myrionecta rubra and the naked dinoflagellates Gyrodinium instriatum and Katodinium glaucum as the main species responsible for this bloom. Total density (microalgae and ciliate) at the sampling stations was similar on both days, varying from 4607 × 103 cells L-1 to 4976 × 103 cells L-1 on the first day, and from 4172 × 103 cells L-1 to 5024 × 103 cells L-1 on the second day. Phytoplankton biomass (chlorophyll a) observed during the first day of the bloom was 1.5 mg m-3. Dinoflagellates and diatoms were the most numerically important phytoplankton groups. The phytoplankton community showed a high species richness, particularly heterotrophic dinoflagellates and ebridians. The ecological importance of the heterotrophic component of naked dinoflagellates and the ebriids for this bay is discussed. Florecimiento multiespecífico de microalgas en la Bahía de La Paz, Golfo de California, México (Junio, 2008) Durante los días 17 y 18 de junio de 2008, se observó una marea roja en la Bahía de La Paz. De acuerdo con los datos de temperatura y de vientos, este florecimiento ocurrió bajo condiciones muy similares a las de una surgencia. El examen de las muestras de marea roja revelaron que el ciliado Myrionecta rubra y los dinoflagelados desnudos Gyrodinium instriatum y Katodinium glaucum fueron las principales especies responsables de esta proliferación. La densidad total (microalgas y ciliado) fue similar en ambos días, variando de 4607 × 103 céls L-1 a 4976 × 103 céls L-1 durante el primero y entre 4172 × 103 céls L-1 y 5024 × 103 céls L-1 el segundo día, respectivamente. La biomasa fitoplanctónica (clorofila a) medida durante el primer día del florecimiento fue de 1.5 mg m3. Los dinoflagelados y las diatomeas fueron los dos grupos del fitoplancton numéricamente más importantes. Se observó una comunidad fitoplanctónica con una alta riqueza de especies, particularmente de dinoflagelados y ebriidos heterotróficos. Se discute la importancia del componente heterotrófico de los dinoflagelados desnudos y ebriidos.

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Bio-optical characterization of the waters of the Bay of La Paz, southern Gulf of California, during late spring 2004

Revista de biología marina y oceanografía ◽

10.22370/rbmo.2019.54.3.2031 ◽

2020 ◽

Vol 54 (3) ◽

pp. 343

Author(s):

Erik Coria-Monter ◽

María Adela Monreal-Gómez ◽

David Alberto Salas de León ◽

Elizabeth Durán-Campos

Keyword(s):

Primary Production ◽

Gulf Of California ◽

Net Primary Production ◽

Light Extinction ◽

La Paz ◽

Light Extinction Coefficient ◽

Production Values ◽

Subsequent Calculation ◽

Natural Fluorescence ◽

Community Growth

Information on selected bio-optical properties and primary production values of the waters of the Bay of La Paz, southern Gulf of California, is reported during June 2004, a region characterized to have very rich biodiversity, including endemic and endangered species, with high ecological relevance. In-situ measurements of natural fluorescence and photosynthetically available radiation (PAR) enabled the subsequent calculation of the incident irradiance (E0), the light extinction coefficient (k), compensation depth (Zc) and critical depth (Zcr). The results suggest the presence of light propitious conditions for phytoplankton community growth and net primary production, which are highly significant for the potential development of models of light penetration, ocean color, primary productivity, and analyses of organic carbon energy flow.

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