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7. Comparative Genomics Supports Ecologically Induced Selection as a Putative Driver of Banded Penguin Diversification.

Author

León, Fabiola, Pizarro, Eduardo, Noll, Daly, Pertierra, Luis R, Parker, Patricia, Espinaze, Marcela P A, Luna-Jorquera, Guillermo, Simeone, Alejandro, Frere, Esteban, Dantas, Gisele P M, Cristofari, Robin, Cornejo, Omar E, Bowie, Rauri C K, and Vianna, Juliana A

Subjects
GENETIC drift, COLONIES (Biology), GENE families, COMPARATIVE genomics, ECOLOGICAL niche
Abstract

The relative importance of genetic drift and local adaptation in facilitating speciation remains unclear. This is particularly true for seabirds, which can disperse over large geographic distances, providing opportunities for intermittent gene flow among distant colonies that span the temperature and salinity gradients of the oceans. Here, we delve into the genomic basis of adaptation and speciation of banded penguins, Galápagos (Spheniscus mendiculus), Humboldt (Spheniscus humboldti), Magellanic (Spheniscus magellanicus), and African penguins (Spheniscus demersus), by analyzing 114 genomes from the main 16 breeding colonies. We aim to identify the molecular mechanism and genomic adaptive traits that have facilitated their diversifications. Through positive selection and gene family expansion analyses, we identified candidate genes that may be related to reproductive isolation processes mediated by ecological thermal niche divergence. We recover signals of positive selection on key loci associated with spermatogenesis, especially during the recent peripatric divergence of the Galápagos penguin from the Humboldt penguin. High temperatures in tropical habitats may have favored selection on loci associated with spermatogenesis to maintain sperm viability, leading to reproductive isolation among young species. Our results suggest that genome-wide selection on loci associated with molecular pathways that underpin thermoregulation, osmoregulation, hypoxia, and social behavior appears to have been crucial in local adaptation of banded penguins. Overall, these results contribute to our understanding of how the complexity of biotic, but especially abiotic, factors, along with the high dispersal capabilities of these marine species, may promote both neutral and adaptive lineage divergence even in the presence of gene flow. [ABSTRACT FROM AUTHOR]

Published
2024
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13. ECOLOGICAL EXPERIENCES AND PERCEPTIONS OF SMALL-SCALE GILLNET AND PURSE SEINE FISHERS ON SEABIRDS AND OTHER NON-TARGET TAXA IN THE HUMBOLDT CURRENT SYSTEM, CHILE.

Author

SUAZO, CRISTIÁN G., ANGUITA, CRISTÓBAL, OJEDA, JAIME, LUNA-JORQUERA, GUILLERMO, SEPÚLVEDA, MARITZA, and YATES, OLIVER

Subjects
PERU Current, SMALL-scale fisheries, PREDATORY aquatic animals, MARINE parks & reserves, SEA lions, ECOSYSTEMS
Abstract

Strategies to reduce the negative impacts of fisheries on ecosystems often come into conflict with fishers who have different experiences with, and perceptions of, biodiversity compared to policy makers and fisheries managers. We interviewed 800 fishers along 2400 kilometers of the Humboldt Current System (HCS) coast, assessing fishers' perceptions of the impacts of marine predators on fishing and their proposals to reduce conflicts with small-scale net fisheries. Vessel captains saw seabirds as positive indicators of fish presence along the HCS (mean probability 62.7%). In contrast, sea lions were perceived negatively, affecting catches for all fishers and causing fishing gear damage among gillnet fishers (97.1%). Among different measures suggested by fishers to reduce conflicts with non-target taxa, night fishing and marine protected areas (MPAs) were viewed as least likely to be implemented because these affect fishing performance (6% and 13.1%) through changes to at-sea safety and fishing effort displacement, respectively. In contrast, economic compensation and culling of currently protected sea lions were the most popular but also the most sensitive measures (31% and 33%, respectively). Different dimensions of experiences and perceptions of fishers are key to the bottom-up understanding of interactions in small-scale fisheries. This is especially true when measures to mitigate their impacts do not have any consolidated installation/monitoring, which is a continuing challenge for these types of fisheries globally. This study emphasizes the role of small-scale fishers as a source of diverse ecological experiences and perceptions to complement knowledge on sensitive conservation issues. [ABSTRACT FROM AUTHOR]

Published
2024

19. Humboldt penguin census on Isla Chañaral, Chile: recent boost in local numbers or past underestimation of population size?

Author

Mattern, Thomas, Ellenberg, Ursula, Luna-Jorquera, Guillermo, and Davis, Lloyd S.

Abstract

While Isla Chañaral (29°02’S) in Chile has long been recognized as one of the most important breeding islands for the Humboldt penguin, its population size reportedly never exceeded 3,500 breeding individuals in the last two decades. However, in 2002 a one-day survey found that the population size on Isla Chañaral may be considerably higher than that and may even exceed the world population estimate for the species (3,300 - 12,000 birds). Between 9 and 14 February 2003 we conducted a population census on Isla Chañaral to determine the number of Humboldt penguins present on the island. Two different census methods were used to assess the population size. Terrestrial or surface counts were used to survey penguins on open plains or beaches. Small area surveys of randomly established counting quadrates were conducted to assess the number of penguins inside nests as well as total number of nests. Results from small area surveys were extrapolated using surface size ratios of counting quadrates vs. entire nesting sectors. From the surface counts and small area surveys we determined that approximately 22,000 adult Humboldt penguins, 3,600 chicks and 117 juveniles were present on the island during the survey. The results were higher than any previously published population estimate, which range from 146 to 6,000 individuals. We conclude that natural processes alone cannot account for a population increase of this magnitude. Furthermore, our results correspond well with recent publications that suggest that Humboldt penguin numbers might have been underestimated in the past due to inconsistent census methods. We are concerned about the current protection status of the island in light of its fragility and importance as the premier breeding location of the Humboldt penguin along its entire distributional range.

Published
2023
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28. Extractivist policies hurt Chile’s ecosystems

Author

Urbina, Mauricio A., primary, Guerrero, Pablo C., additional, Jerez, Viviane, additional, Lisón, Fulgencio, additional, Luna-Jorquera, Guillermo, additional, Matus-Olivares, Camilo, additional, Ortiz, Juan C., additional, Pavez, Guido, additional, Pérez-Alvarez, María J., additional, Riquelme-Bugueño, Ramiro, additional, Santos-Carvallo, Macarena, additional, Sepúlveda, Maritza, additional, Victoriano, Pedro F., additional, and Gomez-Uchida, Daniel, additional

Published
2021
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34. Factors (type, colour, density, and shape) determining the removal of marine plastic debris by seabirds from the South Pacific Ocean: Is there a pattern?

Author

Hidalgo-Ruz, Valeria, Luna-Jorquera, Guillermo, Eriksen, Marcus, Frick, Hanna, Miranda-Urbina, Diego, Portflitt-Toro, Matias, Rivadeneira, Marcelo M., Robertson, Christopher J.R., Scofiels, R. Paul, Serratosa, Juan, Suazo, Cristián G., Thiel, Martin, Hidalgo-Ruz, Valeria, Luna-Jorquera, Guillermo, Eriksen, Marcus, Frick, Hanna, Miranda-Urbina, Diego, Portflitt-Toro, Matias, Rivadeneira, Marcelo M., Robertson, Christopher J.R., Scofiels, R. Paul, Serratosa, Juan, Suazo, Cristián G., and Thiel, Martin

Abstract

1. While floating near the sea surface plastic debris interacts with a number of external factors, including many different organisms. Seabirds have the most extensive documented history of interactions with plastics, through ingestion, entanglement, and nest construction. 2. In the present study, eight seabird species from the South Pacific Ocean were used as a proxy to determine potential patterns of removal of marine plastic debris, and three hypotheses were tested in relation to their feeding habits and nesting areas. 3. Plastics from abiotic compartments (Chilean continental coast, South Pacific Gyre, and Rapa Nui beaches) and biotic compartments (surface‐feeding seabirds, diving seabirds, and nesting areas) were compared, according to their type, colour, shape, and density. 4. Continental beaches had a relatively wide range of colours and shapes, with many non‐buoyant plastics. Samples from the South Pacific Gyre (SPG) and Rapa Nui (Easter Island) beaches comprised mainly hard, rounded, buoyant, and white/grey plastics. 5. These results indicate that the composition of floating plastics from terrestrial sources changes during transport with oceanic currents, reducing the proportion of prey‐like plastics present in the subtropical gyres. 6. The stomach contents of surface‐feeding and diving seabirds were dominated by hard, white/grey, and round plastic items, similar to plastics from the SPG, suggesting non‐selective (accidental or secondary) ingestion. 7. Nesting areas had a more variable composition of brightly coloured plastics, suggesting a pattern of selective removal of plastics by seabirds, probably from oceanic sources. 8. The present study reveals extensive interactions of seabirds with plastics on a broader scale, which is highly relevant given that the impacts of plastics on seabirds are increasing worldwide, compromising their efficient conservation.

Published
2021

37. Factors (type, colour, density, and shape) determining the removal of marine plastic debris by seabirds from the South Pacific Ocean: Is there a pattern?

Author

Hidalgo‐Ruz, Valeria, primary, Luna‐Jorquera, Guillermo, additional, Eriksen, Marcus, additional, Frick, Hanna, additional, Miranda‐Urbina, Diego, additional, Portflitt‐Toro, Matias, additional, Rivadeneira, Marcelo M., additional, Robertson, Christopher J.R., additional, Scofield, R. Paul, additional, Serratosa, Juan, additional, Suazo, Cristián G., additional, and Thiel, Martin, additional

Published
2020
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38. The role of island physiography and oceanographic factors in shaping species richness and turnover of nesting seabird assemblages on islands across the south‐eastern Pacific

Author

Gusmao, Joao B., primary, Luna‐Jorquera, Guillermo, additional, Fernández, Claudia, additional, Luna, Nicolás, additional, Plaza, Paula, additional, Portflitt‐Toro, Matías, additional, Serratosa, Juan, additional, Nuñez, Pamela, additional, Varela, Andrea I., additional, and Rivadeneira, Marcelo M., additional

Published
2020
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39. Genetic diversity, population structure, and historical demography of a highly vagile and human‐impacted seabird in the Pacific Ocean: The red‐tailed tropicbird, Phaethon rubricauda

Author

Varela, Andrea I., primary, Brokordt, Katherina, additional, Ismar‐Rebitz, Stefanie M.H., additional, Gaskin, Chris P., additional, Carlile, Nicholas, additional, O'Dwyer, Terence, additional, Adams, Josh, additional, VanderWerf, Eric A., additional, and Luna‐Jorquera, Guillermo, additional

Published
2020
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41. EVALUACIÓN DEL IMPACTO DE LA CONTAMINACIÓN LUMÍNICA SOBRE LAS AVES MARINAS EN CHILE: DIAGNÓSTICO Y PROPUESTAS

Author

Silva, Rodrigo, primary, Medrano, Fernando, additional, Tejeda, Ivo, additional, Terán, Daniel, additional, Peredo, Ronny, additional, Barros, Rodrigo, additional, Colodro, Valentina, additional, González, Paola, additional, González, Verónica, additional, Guerra-Correa, Carlos, additional, Hodum, Peter, additional, Keitt, Brad, additional, Luna-Jorquera, Guillermo, additional, Malinarich, Vinko, additional, Mallea, Gabriela, additional, Manríquez, Pablo, additional, Nevins, Hannah, additional, Olmedo, Bárbara, additional, Páez-Godoy, Jorge, additional, De Rodt, Guillermo, additional, Rojas, Flora, additional, Sanhueza, Pedro, additional, Suazo, Cristián G., additional, Toro, Frederick, additional, and Toro-Barros, Bárbara, additional

Published
2020
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42. The Humboldt Current System of Northern and Central Chile

Author

Thiel, Martin, primary, Macaya, Erasmo, additional, Acuña, Enzo, additional, Arntz, Wolf, additional, Bastias, Horacio, additional, Brokordt, Katherina, additional, Camus, Patricio, additional, Castilla, Juan, additional, Castro, Leonardo, additional, Cortés, Maritza, additional, Dumont, Clement, additional, Escribano, Ruben, additional, Fernandez, Miriam, additional, Gajardo, Jhon, additional, Gaymer, Carlos, additional, Gomez, Ivan, additional, González, Andrés, additional, González, Humberto, additional, Haye, Pilar, additional, Illanes, Juan-Enrique, additional, Iriarte, Jose, additional, Lancellotti, Domingo, additional, Luna-Jorquera, Guillermo, additional, Luxoro, Carolina, additional, Manriquez, Patricio, additional, Marín, Víctor, additional, Muñoz, Praxedes, additional, Navarrete, Sergio, additional, Perez, Eduardo, additional, Poulin, Elie, additional, Sellanes, Javier, additional, Sepúlveda, Hector, additional, Stotz, Wolfgang, additional, Tala, Fadia, additional, Thomas, Andrew, additional, Vargas, Cristian, additional, Vasquez, Julio, additional, and Vega, Alonso, additional

Published
2007
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44. Factors (type, colour, density, and shape) determining the removal of marine plastic debris by seabirds from the South Pacific Ocean: Is there a pattern?

Author

Hidalgo-Ruz, Valeria, Luna-Jorquera, Guillermo, Eriksen, Marcus, Frick, Hanna, Miranda-Urbina, Diego, Portflitt-Toro, Matias, Rivadeneira, Marcelo M., Robertson, Christopher J.R., Scofiels, R. Paul, Serratosa, Juan, Suazo, Cristián G., Thiel, Martin, Hidalgo-Ruz, Valeria, Luna-Jorquera, Guillermo, Eriksen, Marcus, Frick, Hanna, Miranda-Urbina, Diego, Portflitt-Toro, Matias, Rivadeneira, Marcelo M., Robertson, Christopher J.R., Scofiels, R. Paul, Serratosa, Juan, Suazo, Cristián G., and Thiel, Martin

Abstract

1. While floating near the sea surface plastic debris interacts with a number of external factors, including many different organisms. Seabirds have the most extensive documented history of interactions with plastics, through ingestion, entanglement, and nest construction. 2. In the present study, eight seabird species from the South Pacific Ocean were used as a proxy to determine potential patterns of removal of marine plastic debris, and three hypotheses were tested in relation to their feeding habits and nesting areas. 3. Plastics from abiotic compartments (Chilean continental coast, South Pacific Gyre, and Rapa Nui beaches) and biotic compartments (surface‐feeding seabirds, diving seabirds, and nesting areas) were compared, according to their type, colour, shape, and density. 4. Continental beaches had a relatively wide range of colours and shapes, with many non‐buoyant plastics. Samples from the South Pacific Gyre (SPG) and Rapa Nui (Easter Island) beaches comprised mainly hard, rounded, buoyant, and white/grey plastics. 5. These results indicate that the composition of floating plastics from terrestrial sources changes during transport with oceanic currents, reducing the proportion of prey‐like plastics present in the subtropical gyres. 6. The stomach contents of surface‐feeding and diving seabirds were dominated by hard, white/grey, and round plastic items, similar to plastics from the SPG, suggesting non‐selective (accidental or secondary) ingestion. 7. Nesting areas had a more variable composition of brightly coloured plastics, suggesting a pattern of selective removal of plastics by seabirds, probably from oceanic sources. 8. The present study reveals extensive interactions of seabirds with plastics on a broader scale, which is highly relevant given that the impacts of plastics on seabirds are increasing worldwide, compromising their efficient conservation.

Published
2020

46. Aves marinas varadas en la bahía de Coquimbo, norte de Chile: ¿Qué especies y cuántas mueren?

Author

Portflitt-Toro, Matías, Miranda-Urbina, Diego, and Luna-Jorquera, Guillermo

Subjects
Varamientos, Suliformes, Strandings, Chile, Sistema Costero de Coquimbo, seabirds, Coastal System of Coquimbo, aves marinas
Abstract

Resumen El monitoreo de las aves varadas en las playas puede proporcionar información sobre sus causas de muerte, tales como la captura incidental en actividades de pesca o derrames de petróleo. Durante un año fue monitoreada mensualmente la Bahía de Coquimbo, norte de Chile para cuantificar el número de aves marinas varadas. Se encontraron 395 aves marinas muertas de las cuales 382 fueron identificadas y agrupadas en 21 especies. Las especies más abundantes fueron los piqueros con 115 individuos (30%), el cormorán guanay con 83 individuos (22%) y la gaviota dominicana con 65 individuos (17%). Las especies más abundantes y frecuentes fueron las que anidan en el Sistema Costero de Coquimbo. La mortalidad afecta principalmente a las aves marinas que se alimentan de la anchoveta, que es el principal recurso objetivo de la pesca con redes de cerco. Se sugiere que la mortalidad incidental causada por la pesca es crónica y relativamente constante durante el año. Se requiere un programa de monitoreo a largo plazo para mejorar la estimación de la mortalidad y los factores que influyen en la interacción de las aves marinas con las artes de pesca. Abstract Monitoring of seabirds stranded on beaches can provide information about their causes of death, such as bycatch in fishing activities or oil spills. During a year we monthly monitored the Coquimbo Bay, north Chile, to quantify the number of seabirds and species stranded. We found 395 dead seabirds, of which 382 were identified and grouped into 21 species. The most abundant were the Peruvian booby with 115 individuals (30%), the Guanay cormorant with 83 individuals (22%) and the Kelp gull with 65 individuals (17%). The most abundant and frequent species were those nesting in the Coastal System of Coquimbo. Mortality mainly affected seabirds that feed on anchoveta, which is the main target resource of purse seine fishing. We suggest that the incidental mortality caused by fishing is chronic and relatively constant during the year. A long-term monitoring program is needed to better estimate the mortality and the factors that influence the interaction of seabirds with fishing gears.

Published
2018

49. Uncovering population structure in the Humboldt penguin (Spheniscus humboldti) along the Pacific coast at South America

Author

Dantas, Gisele P. M., primary, Oliveira, Larissa R., additional, Santos, Amanda M., additional, Flores, Mariana D., additional, Melo, Daniella R. de, additional, Simeone, Alejandro, additional, González-Acuña, Daniel, additional, Luna-Jorquera, Guillermo, additional, Le Bohec, Céline, additional, Valdés-Velásquez, Armando, additional, Cardeña, Marco, additional, Morgante, João S., additional, and Vianna, Juliana A., additional

Published
2019
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