Impact of a Mesoscale Cyclonic Eddy on the Phytoplankton Biomass of Bay of La Paz in the Southern Gulf of California

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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Seasonal variability in copepod biomass in a cyclonic eddy in the Bay of La Paz, southern Gulf of California, Mexico

10.1101/2020.03.13.990382 ◽

2020 ◽

Author(s):

Franco Antonio Rocha Díaz ◽

María Adela Monreal Gómez ◽

Erik Coria Monter ◽

David Alberto Salas de León ◽

Elizabeth Durán Campos

Keyword(s):

Water Column ◽

Chlorophyll A ◽

Gulf Of California ◽

Feeding Habits ◽

Mesoscale Eddy ◽

Circulation Pattern ◽

Cyclonic Eddy ◽

La Paz ◽

The Impact ◽

Copepod Biomass

AbstractAs one of the main groups composing marine zooplankton, copepods play an important role due to the position they occupy in the trophic web. Study of their biomass and relationship with the physical conditions of the water column are essential in order to evaluate the trophic structure and functions of any aquatic ecosystem. As a contribution to this topic, we assessed the copepod biomass inside a cyclonic eddy system during two different seasons in the Bay of La Paz in the southern Gulf of California, a region characterized by high biological productivity. Two oceanographic expeditions took place in the winter of 2006 and summer of 2009 on which a conductivity-temperature-depth (CTD) probe was used to determine the physical structure of the water column and oblique zooplankton hauls collected zooplankton samples. Satellite data were used to visualize chlorophyll-a distribution patterns. The results showed the presence of a well-defined mesoscale cyclonic eddy in both seasons, with high chlorophyll-a (CHLA) values at the edges of the eddy. Maximum values for copepod biomass were observed in winter and their distribution corresponded well with the circulation pattern and the CHLA values, forming a belt shape following the periphery of the eddy. The results presented herein highlight the impact of the mesoscale eddy on the planktonic ecosystem through its influence on hydrographic conditions in the water column. Other factors, such as ecological interactions, population dynamics, and feeding habits may play a role as well. Feeding behavior in particular is affected by high CHLA concentrations observed around the eddy which represent a source of food for these organisms.

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Differential distribution of diatoms and dinoflagellates in a cyclonic eddy confined in the Bay of La Paz, Gulf of California

Journal of Geophysical Research Oceans ◽

10.1002/2014jc009916 ◽

2014 ◽

Vol 119 (9) ◽

pp. 6258-6268 ◽

Cited By ~ 18

Author(s):

Erik Coria-Monter ◽

María Adela Monreal-Gómez ◽

David Alberto Salas-de-León ◽

Javier Aldeco-Ramírez ◽

Martín Merino-Ibarra

Keyword(s):

Gulf Of California ◽

Cyclonic Eddy ◽

Differential Distribution ◽

La Paz

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

Diversity ◽

10.3390/d13050212 ◽

2021 ◽

Vol 13 (5) ◽

pp. 212

Author(s):

Francisco Javier Urcádiz-Cázares ◽

Víctor Hugo Cruz-Escalona ◽

Mark S. Peterson ◽

Rosalía Aguilar-Medrano ◽

Emigdio Marín-Enríquez ◽

...

Keyword(s):

Gulf Of California ◽

Management Plan ◽

Marine Conservation ◽

Fish Diversity ◽

Rocky Shores ◽

Conservation Areas ◽

Niche Modelling ◽

La Paz ◽

Abiotic Conditions ◽

Presence Data

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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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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Polycyclic aromatic hydrocarbons (PAHs) in mussels (Modiolus capax) from sites with increasing anthropogenic impact in La Paz Bay, Gulf of California

Regional Studies in Marine Science ◽

10.1016/j.rsma.2019.100948 ◽

2020 ◽

Vol 33 ◽

pp. 100948

Author(s):

Nefertiti Taydé Roldán-Wong ◽

Karen A. Kidd ◽

Bertha Patricia Ceballos-Vázquez ◽

Alma Rosa Rivera-Camacho ◽

Marcial Arellano-Martínez

Keyword(s):

Polycyclic Aromatic Hydrocarbons ◽

Aromatic Hydrocarbons ◽

Gulf Of California ◽

Anthropogenic Impact ◽

La Paz ◽

Polycyclic Aromatic

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Taxonomy and diversity of Hydrozoa (Cnidaria, Medusozoa) of La Paz Bay, Gulf of California

Zootaxa ◽

10.11646/zootaxa.4808.1.1 ◽

2020 ◽

Vol 4808 (1) ◽

pp. 1-37

Author(s):

MARÍA A. MENDOZA-BECERRIL ◽

MARIAE C. ESTRADA-GONZÁLEZ ◽

ALEJANDRA MAZARIEGOS-VILLARREAL ◽

LUISA RESTREPO-AVENDAÑO ◽

ROGELIO D. VILLAR-BELTRÁN ◽

...

Keyword(s):

Phylogenetic Relationships ◽

Gulf Of California ◽

New Records ◽

Species Boundaries ◽

La Paz ◽

Mexican Pacific ◽

Taxonomic Descriptions

The Mexican Pacific has been the focus of several research expeditions, with 90 species of hydromedusae and more than 200 species of hydroids recorded for the region. However, only a few of these reports include taxonomic descriptions, hindering inferences of the phylogenetic relationships, species boundaries, and diversity of Hydrozoa in Mexican waters. In this study, we present detailed and illustrated descriptions of new records of hydromedusae and hydroids for La Paz Bay, Gulf of California. We found a total of 16 species comprising 15 genera, with three new records for the Gulf of California (polyps of Antennella secundaria, Bimeria vestita, and Ventromma halecioides), two new records for the Mexican Pacific (medusa of Clytia linearis, polyp of Halopteris violae), and we redescribe Obelia tenuis. We show that the diversity of Hydrozoa in the Mexican Pacific is likely underestimated, and we emphasize the importance of taxonomic and systematic studies of hydroids and hydromedusae in Mexico.

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