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1. Exploring the Predictability of EEG Signals Timed with the Heartbeat: A Model-Based Approach for the Temporal and Spatial Characterization of the Brain Dynamics

Author

Vergara, Valeria Rosalia, Bara, Chiara, Pernice, Riccardo, Zaccaro, Andrea, Ferri, Francesca, Faes, Luca, Antonacci, Yuri, Magjarević, Ratko, Series Editor, Ładyżyński, Piotr, Associate Editor, Ibrahim, Fatimah, Associate Editor, Lackovic, Igor, Associate Editor, Rock, Emilio Sacristan, Associate Editor, Badnjević, Almir, editor, and Gurbeta Pokvić, Lejla, editor

Published
2024
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2. Global COVID-19 lockdown highlights humans as both threats and custodians of the environment

Author

Bates, Amanda E, Primack, Richard B, Biggar, Brandy S, Bird, Tomas J, Clinton, Mary E, Command, Rylan J, Richards, Cerren, Shellard, Marc, Geraldi, Nathan R, Vergara, Valeria, Acevedo-Charry, Orlando, Colón-Piñeiro, Zuania, Ocampo, David, Ocampo-Peñuela, Natalia, Sánchez-Clavijo, Lina M, Adamescu, Cristian M, Cheval, Sorin, Racoviceanu, Tudor, Adams, Matthew D, Kalisa, Egide, Kuuire, Vincent Z, Aditya, Vikram, Anderwald, Pia, Wiesmann, Samuel, Wipf, Sonja, Badihi, Gal, Henderson, Matthew G, Loetscher, Hanspeter, Baerenfaller, Katja, Benedetti-Cecchi, Lisandro, Bulleri, Fabio, Bertocci, Iacopo, Maggi, Elena, Rindi, Luca, Ravaglioli, Chiara, Boerder, Kristina, Bonnel, Julien, Mathias, Delphine, Archambault, Philippe, Chauvaud, Laurent, Braun, Camrin D, Thorrold, Simon R, Brownscombe, Jacob W, Midwood, Jonathan D, Boston, Christine M, Brooks, Jill L, Cooke, Steven J, China, Victor, Roll, Uri, Belmaker, Jonathan, Zvuloni, Assaf, Coll, Marta, Ortega, Miquel, Connors, Brendan, Lacko, Lisa, Jayathilake, Dinusha RM, Costello, Mark J, Crimmins, Theresa M, Barnett, LoriAnne, Denny, Ellen G, Gerst, Katharine L, Marsh, RL, Posthumus, Erin E, Rodriguez, Reilly, Rosemartin, Alyssa, Schaffer, Sara N, Switzer, Jeff R, Wong, Kevin, Cunningham, Susan J, Sumasgutner, Petra, Amar, Arjun, Thomson, Robert L, Stofberg, Miqkayla, Hofmeyr, Sally, Suri, Jessleena, Stuart-Smith, Rick D, Day, Paul B, Edgar, Graham J, Cooper, Antonia T, De Leo, Fabio Cabrera, Garner, Grant, Brisay, Paulson G Des, Schrimpf, Michael B, Koper, Nicola, Diamond, Michael S, Dwyer, Ross G, Baker, Cameron J, Franklin, Craig E, Efrat, Ron, Berger-Tal, Oded, Hatzofe, Ohad, Eguíluz, Víctor M, Rodríguez, Jorge P, Fernández-Gracia, Juan, Elustondo, David, Calatayud, Vicent, English, Philina A, Archer, Stephanie K, Dudas, Sarah E, and Haggarty, Dana R

Subjects
Life on Land, Pandemic, Biodiversity, Restoration, Global monitoring, Environmental Sciences, Biological Sciences, Agricultural and Veterinary Sciences, Ecology
Abstract

The global lockdown to mitigate COVID-19 pandemic health risks has altered human interactions with nature. Here, we report immediate impacts of changes in human activities on wildlife and environmental threats during the early lockdown months of 2020, based on 877 qualitative reports and 332 quantitative assessments from 89 different studies. Hundreds of reports of unusual species observations from around the world suggest that animals quickly responded to the reductions in human presence. However, negative effects of lockdown on conservation also emerged, as confinement resulted in some park officials being unable to perform conservation, restoration and enforcement tasks, resulting in local increases in illegal activities such as hunting. Overall, there is a complex mixture of positive and negative effects of the pandemic lockdown on nature, all of which have the potential to lead to cascading responses which in turn impact wildlife and nature conservation. While the net effect of the lockdown will need to be assessed over years as data becomes available and persistent effects emerge, immediate responses were detected across the world. Thus, initial qualitative and quantitative data arising from this serendipitous global quasi-experimental perturbation highlights the dual role that humans play in threatening and protecting species and ecosystems. Pathways to favorably tilt this delicate balance include reducing impacts and increasing conservation effectiveness.

Published
2021

4. Call Usage Learning by a Beluga (Delphinapterus leucas) in a Categorical Matching Task

Author

Vergara, Valeria and Barrett-Lennard, Lance

Subjects
categorical matching, categorization, contextual learning, vocal learning, belugas, Delphinapterus leucas
Abstract

The ability to modify the structure and context of vocalizations through learning plays a key role in the social interactions of many species.  The investigation of categorical matching, an aspect of contextual vocal learning, is the first step toward determining how contextual learning plays a role in the use, comprehension, and categorization of sounds in the wild.  To this end, we conducted a study at the Vancouver Aquarium to test the ability of a juvenile female beluga, Qila, to respond to playbacks of two types of in-air beluga calls with vocalizations that matched the category of call played (a scream, which is a vocalization type shaped over time with reinforcement and not part of this species'natural repertoire, and a pulse-train, a natural call category).  We first tested Qila with random sequences of the same version of the two vocalizations with which she had been trained.  Her overall success in matching all playback stimuli was above chance but not statistically so (66%).  She had more difficulty matching screams (54% success) than pulse trains (80% success).  We next played random sequences of six novel pulse-trains and seven novel screams, which Qila had not been trained with.  She responded correctly to the set of novel stimuli of both call types in 64% of the trials, a success rate that did not differ statistically from chance.  Again, she had more difficulty matching screams (55% success), relative to pulse trains (74% success).  These results indicate that Qila successfully matched only pulse trains, the class that is part of this species’ natural repertoire.  Her poor performance on matching screams might be partly explained by a difficulty to perceive categorically a signal that lacks a function in the natural repertoire of belugas.Keywords: categorical matching, contextual learning, vocal learning, categorization, belugas

Published
2017

7. Geographic variation in simple contact calls of Canadian beluga whales (Delphinapterus leucas).

Author

Booy, Karyn V., Vergara, Valeria, Loseto, Lisa, Mikus, Marie‐Ana, and Marcoux, Marianne

Subjects
WHITE whale, DISCRIMINANT analysis, WHALES, GENETIC variation, MULTIVARIATE analysis
Abstract

Beluga whales, Delphinapterus leucas, are a highly social species with a complex and diverse vocal repertoire. Although extensively studied and classified, to date few attempts have been made to examine geographic variation in their calls. In this study, we examined geographic variation in simple contact calls (SCCs), specifically those that consist only of broadband pulsed trains, among four Canadian beluga populations from the Eastern Beaufort Sea (EBS), the Eastern High Arctic‐Baffin Bay, St. Lawrence Estuary (SLE), and the Western Hudson Bay. Five acoustic parameters were measured for each call and compared among populations using multivariate discriminant analysis. Results of our study indicate that there is a degree of variation in SCCs among these four populations, with the most geographically distant populations of the SLE and EBS displaying the greatest degrees of dissimilarity in SCC structure relative to geographically closer populations. Further, these results align with genetic variation of Canadian beluga populations previously described in the literature. This study is the first descriptive population comparison of SCCs for beluga and establishes a baseline for continued work into this developing area of research. [ABSTRACT FROM AUTHOR]

Published
2024
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8. What can Captive Whales tell us About their Wild Counterparts? Identification, Usage, and Ontogeny of Contact Calls in Belugas (Delphinapterus leucas)

Author

Vergara, Valeria, Michaud, Robert, and Barrett-Lennard, Lance

Subjects
International Journal of Comparative Psychology, Behavior, Behaviour, Communication, Vocalization, Learning, Behavioral Taxonomy, Cognition, Cognitive Processes, Intelligence, Choice, Conditioning, Language, Calling, Whales, Beluga, Whale
Abstract

Contact calls are ubiquitous in social birds and mammals. Belugas are among the most vocal of cetaceans, but the function of their calls is poorly understood. In a previous study we hypothesized that a broad band pulsed call type labeled “Type A,” serves as a contact call between mothers and their calves. Here we examined context-specific use of call types recorded from a captive beluga social group at the Vancouver Aquarium, and found that the Type A call comprised 24% to 97% of the vocalizations during isolation, births, death of a calf, presence of external stressors, and re-union of animals after separation. In contrast it comprised 4.4% of the vocalizations produced during regular sessions. We grouped 2835 Type A calls into five variants, A1 to A5. A discriminant function analysis classified 87% of calls in the same groupings that we assigned them to by ear and visual examination of spectrograms. The variants do not represent individual signatures. One variant, A1, was used by three related individuals: an adult female, her male calf and his juvenile half-sister. Our previous research documented the gradual development of the A1 variant by the male calf, until at 20 months he was producing stereotyped renditions of his mother and sister’s A1. We used our findings to generate testable predictions about the usage of these signals by wild belugas. We verified the existence of signals with the same distinctive features as the contact calls found in captivity in the repertoire of St. Lawrence Estuary herds, and documented their usage by two wild individuals from different populations. In the St. Lawrence, these were emitted by a female calling after a dead-calf. In Hudson Bay, by a temporarily restrained juvenile. We propose that these calls function in nature, a sin captivity, to maintain group cohesion, and that the variants shared by related animals are used for mother-calf recognition.

Published
2010

12. Global COVID-19 lockdown highlights humans as both threats and custodians of the environment

Author

Bates, Amanda E., primary, Primack, Richard B., additional, Biggar, Brandy S., additional, Bird, Tomas J., additional, Clinton, Mary E., additional, Command, Rylan J., additional, Richards, Cerren, additional, Shellard, Marc, additional, Geraldi, Nathan R., additional, Vergara, Valeria, additional, Acevedo-Charry, Orlando, additional, Colón-Piñeiro, Zuania, additional, Ocampo, David, additional, Ocampo-Peñuela, Natalia, additional, Sánchez-Clavijo, Lina M., additional, Adamescu, Cristian M., additional, Cheval, Sorin, additional, Racoviceanu, Tudor, additional, Adams, Matthew D., additional, Kalisa, Egide, additional, Kuuire, Vincent Z., additional, Aditya, Vikram, additional, Anderwald, Pia, additional, Wiesmann, Samuel, additional, Wipf, Sonja, additional, Badihi, Gal, additional, Henderson, Matthew G., additional, Loetscher, Hanspeter, additional, Baerenfaller, Katja, additional, Benedetti-Cecchi, Lisandro, additional, Bulleri, Fabio, additional, Bertocci, Iacopo, additional, Maggi, Elena, additional, Rindi, Luca, additional, Ravaglioli, Chiara, additional, Boerder, Kristina, additional, Bonnel, Julien, additional, Mathias, Delphine, additional, Archambault, Philippe, additional, Chauvaud, Laurent, additional, Braun, Camrin D., additional, Thorrold, Simon R., additional, Brownscombe, Jacob W., additional, Midwood, Jonathan D., additional, Boston, Christine M., additional, Brooks, Jill L., additional, Cooke, Steven J., additional, China, Victor, additional, Roll, Uri, additional, Belmaker, Jonathan, additional, Zvuloni, Assaf, additional, Coll, Marta, additional, Ortega, Miquel, additional, Connors, Brendan, additional, Lacko, Lisa, additional, Jayathilake, Dinusha R.M., additional, Costello, Mark J., additional, Crimmins, Theresa M., additional, Barnett, LoriAnne, additional, Denny, Ellen G., additional, Gerst, Katharine L., additional, Marsh, R.L., additional, Posthumus, Erin E., additional, Rodriguez, Reilly, additional, Rosemartin, Alyssa, additional, Schaffer, Sara N., additional, Switzer, Jeff R., additional, Wong, Kevin, additional, Cunningham, Susan J., additional, Sumasgutner, Petra, additional, Amar, Arjun, additional, Thomson, Robert L., additional, Stofberg, Miqkayla, additional, Hofmeyr, Sally, additional, Suri, Jessleena, additional, Stuart-Smith, Rick D., additional, Day, Paul B., additional, Edgar, Graham J., additional, Cooper, Antonia T., additional, De Leo, Fabio Cabrera, additional, Garner, Grant, additional, Des Brisay, Paulson G., additional, Schrimpf, Michael B., additional, Koper, Nicola, additional, Diamond, Michael S., additional, Dwyer, Ross G., additional, Baker, Cameron J., additional, Franklin, Craig E., additional, Efrat, Ron, additional, Berger-Tal, Oded, additional, Hatzofe, Ohad, additional, Eguíluz, Víctor M., additional, Rodríguez, Jorge P., additional, Fernández-Gracia, Juan, additional, Elustondo, David, additional, Calatayud, Vicent, additional, English, Philina A., additional, Archer, Stephanie K., additional, Dudas, Sarah E., additional, Haggarty, Dana R., additional, Gallagher, Austin J., additional, Shea, Brendan D., additional, Shipley, Oliver N., additional, Gilby, Ben L., additional, Ballantyne, Jasmine, additional, Olds, Andrew D., additional, Henderson, Christopher J., additional, Schlacher, Thomas A., additional, Halliday, William D., additional, Brown, Nicholas A.W., additional, Woods, Mackenzie B., additional, Balshine, Sigal, additional, Juanes, Francis, additional, Rider, Mitchell J., additional, Albano, Patricia S., additional, Hammerschlag, Neil, additional, Hays, Graeme C., additional, Esteban, Nicole, additional, Pan, Yuhang, additional, He, Guojun, additional, Tanaka, Takanao, additional, Hensel, Marc J.S., additional, Orth, Robert J., additional, Patrick, Christopher J., additional, Hentati-Sundberg, Jonas, additional, Olsson, Olof, additional, Hessing-Lewis, Margot L., additional, Higgs, Nicholas D., additional, Hindell, Mark A., additional, McMahon, Clive R., additional, Harcourt, Rob, additional, Guinet, Christophe, additional, Hirsch, Sarah E., additional, Perrault, Justin R., additional, Hoover, Shelby R., additional, Reilly, Jennifer D., additional, Hobaiter, Catherine, additional, Gruber, Thibaud, additional, Huveneers, Charlie, additional, Udyawer, Vinay, additional, Clarke, Thomas M., additional, Kroesen, Laura P., additional, Hik, David S., additional, Cherry, Seth G., additional, Del Bel Belluz, Justin A., additional, Jackson, Jennifer M., additional, Lai, Shengjie, additional, Lamb, Clayton T., additional, LeClair, Gregory D., additional, Parmelee, Jeffrey R., additional, Chatfield, Matthew W.H., additional, Frederick, Cheryl A., additional, Lee, Sangdon, additional, Park, Hyomin, additional, Choi, Jaein, additional, LeTourneux, Frédéric, additional, Grandmont, Thierry, additional, de-Broin, Frédéric Dulude, additional, Bêty, Joël, additional, Gauthier, Gilles, additional, Legagneux, Pierre, additional, Lewis, Jesse S., additional, Haight, Jeffrey, additional, Liu, Zhu, additional, Lyon, Jarod P., additional, Hale, Robin, additional, D'Silva, Dallas, additional, MacGregor-Fors, Ian, additional, Arbeláez-Cortés, Enrique, additional, Estela, Felipe A., additional, Sánchez-Sarria, Camilo E., additional, García-Arroyo, Michelle, additional, Aguirre-Samboní, Giann K., additional, Franco Morales, Juan C., additional, Malamud, Shahar, additional, Gavriel, Tal, additional, Buba, Yehezkel, additional, Salingré, Shira, additional, Lazarus, Mai, additional, Yahel, Ruthy, additional, Ari, Yigael Ben, additional, Miller, Eyal, additional, Sade, Rotem, additional, Lavian, Guy, additional, Birman, Ziv, additional, Gury, Manor, additional, Baz, Harel, additional, Baskin, Ilia, additional, Penn, Alon, additional, Dolev, Amit, additional, Licht, Ogen, additional, Karkom, Tabi, additional, Davidzon, Sharon, additional, Berkovitch, Avi, additional, Yaakov, Ofer, additional, Manenti, Raoul, additional, Mori, Emiliano, additional, Ficetola, Gentile Francesco, additional, Lunghi, Enrico, additional, March, David, additional, Godley, Brendan J., additional, Martin, Cecilia, additional, Mihaly, Steven F., additional, Barclay, David R., additional, Thomson, Dugald J.M., additional, Dewey, Richard, additional, Bedard, Jeannette, additional, Miller, Aroha, additional, Dearden, Amber, additional, Chapman, Jennifer, additional, Dares, Lauren, additional, Borden, Laura, additional, Gibbs, Donna, additional, Schultz, Jessica, additional, Sergeenko, Nikita, additional, Francis, Fiona, additional, Weltman, Amanda, additional, Moity, Nicolas, additional, Ramírez-González, Jorge, additional, Mucientes, Gonzalo, additional, Alonso-Fernández, Alexandre, additional, Namir, Itai, additional, Bar-Massada, Avi, additional, Chen, Ron, additional, Yedvab, Shmulik, additional, Okey, Thomas A., additional, Oppel, Steffen, additional, Arkumarev, Volen, additional, Bakari, Samuel, additional, Dobrev, Vladimir, additional, Saravia-Mullin, Victoria, additional, Bounas, Anastasios, additional, Dobrev, Dobromir, additional, Kret, Elzbieta, additional, Mengistu, Solomon, additional, Pourchier, Cloé, additional, Ruffo, Alazar, additional, Tesfaye, Million, additional, Wondafrash, Mengistu, additional, Nikolov, Stoyan C., additional, Palmer, Charles, additional, Sileci, Lorenzo, additional, Rex, Patrick T., additional, Lowe, Christopher G., additional, Peters, Francesc, additional, Pine, Matthew K., additional, Radford, Craig A., additional, Wilson, Louise, additional, McWhinnie, Lauren, additional, Scuderi, Alessia, additional, Jeffs, Andrew G., additional, Prudic, Kathleen L., additional, Larrivée, Maxim, additional, McFarland, Kent P., additional, Solis, Rodrigo, additional, Hutchinson, Rebecca A., additional, Queiroz, Nuno, additional, Furtado, Miguel A., additional, Sims, David W., additional, Southall, Emily, additional, Quesada-Rodriguez, Claudio A., additional, Diaz-Orozco, Jessica P., additional, Rodgers, Ku'ulei S., additional, Severino, Sarah J.L., additional, Graham, Andrew T., additional, Stefanak, Matthew P., additional, Madin, Elizabeth M.P., additional, Ryan, Peter G., additional, Maclean, Kyle, additional, Weideman, Eleanor A., additional, Şekercioğlu, Çağan H., additional, Kittelberger, Kyle D., additional, Kusak, Josip, additional, Seminoff, Jeffrey A., additional, Hanna, Megan E., additional, Shimada, Takahiro, additional, Meekan, Mark G., additional, Smith, Martin K.S., additional, Mokhatla, Mohlamatsane M., additional, Soh, Malcolm C.K., additional, Pang, Roanna Y.T., additional, Ng, Breyl X.K., additional, Lee, Benjamin P.Y.-H., additional, Loo, Adrian H.B., additional, Er, Kenneth B.H., additional, Souza, Gabriel B.G., additional, Stallings, Christopher D., additional, Curtis, Joseph S., additional, Faletti, Meaghan E., additional, Peake, Jonathan A., additional, Schram, Michael J., additional, Wall, Kara R., additional, Terry, Carina, additional, Rothendler, Matt, additional, Zipf, Lucy, additional, Ulloa, Juan Sebastián, additional, Hernández-Palma, Angélica, additional, Gómez-Valencia, Bibiana, additional, Cruz-Rodríguez, Cristian, additional, Herrera-Varón, Yenifer, additional, Roa, Margarita, additional, Rodríguez-Buriticá, Susana, additional, Ochoa-Quintero, Jose Manuel, additional, Vardi, Reut, additional, Vázquez, Víctor, additional, Requena-Mesa, Christian, additional, Warrington, Miyako H., additional, Taylor, Michelle E., additional, Woodall, Lucy C., additional, Stefanoudis, Paris V., additional, Zhang, Xiangliang, additional, Yang, Qiang, additional, Zukerman, Yuval, additional, Sigal, Zehava, additional, Ayali, Amir, additional, Clua, Eric E.G., additional, Carzon, Pamela, additional, Seguine, Clementine, additional, Corradini, Andrea, additional, Pedrotti, Luca, additional, Foley, Catherine M., additional, Gagnon, Catherine Alexandra, additional, Panipakoochoo, Elijah, additional, Milanes, Celene B., additional, Botero, Camilo M., additional, Velázquez, Yunior R., additional, Milchakova, Nataliya A., additional, Morley, Simon A., additional, Martin, Stephanie M., additional, Nanni, Veronica, additional, Otero, Tanya, additional, Wakeling, Julia, additional, Abarro, Sarah, additional, Piou, Cyril, additional, Sobral, Ana F.L., additional, Soto, Eulogio H., additional, Weigel, Emily G., additional, Bernal-Ibáñez, Alejandro, additional, Gestoso, Ignacio, additional, Cacabelos, Eva, additional, Cagnacci, Francesca, additional, Devassy, Reny P., additional, Loretto, Matthias-Claudio, additional, Moraga, Paula, additional, Rutz, Christian, additional, and Duarte, Carlos M., additional

Published
2021
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14. Rasgos prosódicos de oraciones sin expansión, del español de Santiago de Chile en habla femenina

Author

Montes De Oca, Domingo Román, Cofré Vergara, Valeria, and Rosas Aguilar, Claudia

Abstract

En este estudio se indagan las principales características prosódicas del español de Santiago de Chile en el contexto investigativo del proyecto AMPER. En particular, se estudian las oraciones enunciativas e interrogativas sin expansión ni en el sujeto ni en el predicado. Se presentan los resultados en términos de frecuencia fundamental, duración y energía. Se concluye que las enunciativas presentan dos picos frecuenciales, que corresponden al primer y segundo acento, en tanto que en las interrogativas hay solo uno, que corresponde al primer acento. En términos de duración, en los acentos interiores es la sílaba tónica la de mayor prominencia; en tanto que en el acento final, es la última vocal la más larga. En cuanto a la energía, en el final del enunciado se encuentran los valores más bajos; los valores altos en algunos casos coinciden con la sílaba tónica pero a este respecto hay bastante variedad.

Published
2021

15. Global COVID-19 lockdown highlights humans as both threats and custodians of the environment

Author

Bates, Amanda E., Primack, Richard B., Biggar, Brandy S., Bird, Tomas J., Clinton, Mary E., Command, Rylan J., Richards, Cerren, Shellard, Marc, Geraldi, Nathan R., Vergara, Valeria, Acevedo-Charry, Orlando, Colón-Piñeiro, Zuania, Ocampo, David, Ocampo-Peñuela, Natalia, Sánchez-Clavijo, Lina M., Adamescu, Cristian M., Cheval, Sorin, Racoviceanu, Tudor, Adams, Matthew D., Kalisa, Egide, Kuuire, Vincent Z., Aditya, Vikram, Anderwald, Pia, Wiesmann, Samuel, ..., ..., Morley, Simon A., ..., et al, Bates, Amanda E., Primack, Richard B., Biggar, Brandy S., Bird, Tomas J., Clinton, Mary E., Command, Rylan J., Richards, Cerren, Shellard, Marc, Geraldi, Nathan R., Vergara, Valeria, Acevedo-Charry, Orlando, Colón-Piñeiro, Zuania, Ocampo, David, Ocampo-Peñuela, Natalia, Sánchez-Clavijo, Lina M., Adamescu, Cristian M., Cheval, Sorin, Racoviceanu, Tudor, Adams, Matthew D., Kalisa, Egide, Kuuire, Vincent Z., Aditya, Vikram, Anderwald, Pia, Wiesmann, Samuel, ..., ..., Morley, Simon A., and ..., et al

Abstract

The global lockdown to mitigate COVID-19 pandemic health risks has altered human interactions with nature. Here, we report immediate impacts of changes in human activities on wildlife and environmental threats during the early lockdown months of 2020, based on 877 qualitative reports and 332 quantitative assessments from 89 different studies. Hundreds of reports of unusual species observations from around the world suggest that animals quickly responded to the reductions in human presence. However, negative effects of lockdown on conservation also emerged, as confinement resulted in some park officials being unable to perform conservation, restoration and enforcement tasks, resulting in local increases in illegal activities such as hunting. Overall, there is a complex mixture of positive and negative effects of the pandemic lockdown on nature, all of which have the potential to lead to cascading responses which in turn impact wildlife and nature conservation. While the net effect of the lockdown will need to be assessed over years as data becomes available and persistent effects emerge, immediate responses were detected across the world. Thus, initial qualitative and quantitative data arising from this serendipitous global quasi-experimental perturbation highlights the dual role that humans play in threatening and protecting species and ecosystems. Pathways to favorably tilt this delicate balance include reducing impacts and increasing conservation effectiveness.

Published
2021

16. Verseando

Author

Meneses Cabrera, Tania, Universidad Nacional Abierta y a Distancia (UNAD), Latierro, Arturo, Chona, Carmen Liliana, Pertierra, Rosa, Peña, Vilma, López Arciniegas, Nicolás Andrés, Vergara, Valeria, Ordoñez, Adriana, Pulido, Lyda Constanza, Macías, Andrés Felipe, Casillas Zuzuarregui, Ana, Perea Sandoval, Carlos, and Peña Trujillo, Jaime Enrique

Subjects
poemas, versos, literatura
Abstract

Verseando, es un trabajo colaborativo en el que participan lectores de poesía que se arriesgaron a salir del cómodo lugar tras el libro, aunque quieren continuar con algo de anonimato sobre sus vidas, solo nos cuentan sobre su lugar de origen y sus sentires. Se arriesgaron a ser juzgados y escribir, hay de todo, cada quien con sus historias, en verso o en fotografía como metáfora de versos libres. Todas son almas aprendices de vida y poesía.

Published
2019

18. Codificación prosódica del foco oracional en narraciones infantiles en el español de Chile: un estudio exploratorio.

Author

Cofré Vergara, Valeria and Álvarez, Fernando

Subjects
*LANGUAGE acquisition, *PROSODIC analysis (Linguistics), *SPANISH language, *VOWELS, *ADULTS
Abstract

In this research, we analyze the development of prosodic features to organize information and highlight sentence focus in semi-spontaneous narratives of children between 4 and 10 years old. We conducted experimental research with three children from Santiago de Chile aged 5, 7, and 9 years. We identified representative features of different stages of language development and, thus, proposed a hypothesis regarding the development of prosodic codification of the focus. We acoustically analyzed the segmented clauses for pitch alignment, pitch excrusion, and vowel duration with the nuclear focus stress. As to the prosodic coding of focus, specifically regarding pitch and duration, this study shows emerging features of a phonological adult model of accent assignment and alignment of the tonal peak, but with phonetic variation among children of different ages, specifically regarding pitch high and duration of the tonic syllable. These findings are new within the framework of the study of language development in Spanish and shed light on the phonetic development of prosody. [ABSTRACT FROM AUTHOR]

Published
2022

22. Contact call diversity in natural beluga entrapments in an Arctic estuary: Preliminary evidence of vocal signatures in wild belugas.

Author

Vergara, Valeria and Mikus, Marie‐Ana

Subjects
WHITE whale, MARINE mammals, BOTTLENOSE dolphin, VOCALIZATION in mammals, DELPHINAPTERUS
Abstract

Broadband, pulsed contact calls have been described for captive and temporarily restrained belugas, but little information exists on their usage in the wild. We examined vocal production during 14 natural beluga entrapments in a shallow channel in Cunningham Inlet, as isolation events offer ideal contexts to study contact calls. Drone footage, overhead photos, and shore‐based photos confirmed the number of individuals and age composition in each entrapment. Contact calls comprised the majority (61%) of vocalizations produced by entrapped whales compared to the free‐ranging herd (10%). We divided contact calls into complex (80%), those with a stereotyped, spectrographically prominent component overlapping the pulse train that characterizes all beluga contact calls, and simple (20%), those with no overlapping component. For each entrapment, we generated a catalogue of complex contact call types, totaling 87 types. Our classification was corroborated both quantitatively and by 55 naïve human judges. Occasional instances of overlapping contact calls of the same type indicated dyadic production. The number of contact call types per entrapment was strongly related to (never exceeding) the number of individuals, excluding neonates. Although this suggests a system of vocal signatures in belugas, consistent with their fission‐fusion society and earlier findings, whether signature identity is encoded individually or shared with related animals remains unknown. [ABSTRACT FROM AUTHOR]

Published
2019
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24. Acoustic communication and vocal learning in belugas (Delphinapterus leucas)

Author

Vergara, Valeria

Abstract

Belugas (Delphinapterus leucas) are highly vocal cetaceans, but the function of their calls, repertoire ontogeny, and role of learning in vocal behavior are poorly understood. This dissertation examines these issues, focusing on a captive beluga group at the Vancouver Aquarium. First, I investigated vocal development in a beluga calf, longitudinally throughout his first year of life, and later opportunistically. The first sounds after birth were low energy, broadband pulse-trains, which increased in pulse repetition rate with age. He incorporated rudimentary whistles at two weeks. His mixed calls, which became consistent at four months, became progressively stereotyped, increasingly like his mother’s “Type-A” call, a presumed contact call. Six months after he was first exposed to his father’s calls, he developed a call type similar to one of his father’s. I discuss these findings in light of theories of sound production mechanisms, developmental stages of vocal acquisition, and vocal learning. Secondly, I examined context-specific use of call types recorded from the beluga group, with particular focus on the Type-A call. This signal constituted 24-97% of the vocalizations during isolation, births, deaths, presence of external stressors, and re-union of animals after separation. In contrast, it represented 4.4% of the vocalizations during regular sessions. I identified five Type-A variants subjectively and quantitatively. I used these findings to generate hypotheses about the usage of these signals by wild belugas, verified the existence of A-calls in the repertoire of St. Lawrence herds, and documented their usage by two wild individuals from different populations in contexts that supported their contact function. Finally, I investigated contextual vocal learning in trained tasks in adult belugas, focusing on the ability of a female beluga to respond to playbacks of two categories of beluga calls with matching vocalizations; pulse-trains are a natural category, and screams an artificial class shaped by training. The subject successfully matched only pulse-trains, the class that is part of this species’ natural repertoire. Her poor performance on matching screams might be partly explained by a difficulty to perceive categorically a signal that lacks a function in the natural repertoire of belugas.

Published
2011
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