Key words: marine debris, Gulf of California, secondary ingestion, Red-billed Tropicbird, wire ingestion
    
    
    
    
      References
      
        
      
        Almaguer-Hernández, A. M. (2016). Ecología Reproductiva y Trófica del Rabijunco Pico Rojo Phaethon aethereus (Linnaeus, 1758) en la Isla Peña Blanca, Colima, México [Bachelor's thesis, Universidad de Guadalajara].
 
      
        Altschul, S. F., Gish, W., Miller, W., Myers, E. W., & Lipman, D. J. (1990). Basic local alignment search tool. 
Journal of Molecular Biology, 215(3), 403-410. 
https://doi.org/10.1016/S0022-2836(05)80360-2
 Barrett, R. T., Camphuysen, C. J., Anker-Nilssen, T., Chardine, J. W., Furness, R. W., Garthe, S., Hüppop, O., Leopold, M. F., Montevecchi, W. A., & Veit, R. R. (2007). Diet studies of seabirds: A review and recommendations. 
ICES Journal of Marine Science, 64(9), 1675-1691. 
https://doi.org/10.1093/icesjms/fsm152
 Beal, M., Oppel, S., Handley, J., Pearmain, E. J., Morera-Pujol, V., Carneiro, A. P. B., Davies, T. E., Phillips, R. A., Taylor, P. R., Miller, M. G. R., Franco, A. M. A., Catry, I., Patrício, A. R., Regalla, A., Staniland, I., Boyd, C., Catry, P., & Dias, M. P. (2021). track2KBA: An R package for identifying important sites for biodiversity from tracking data. 
Methods in Ecology and Evolution, 12(12), 2372-2378. 
https://doi.org/10.1111/2041-210X.13713
 Berry, T. E., Osterrieder, S. K., Murray, D. C., Coghlan, M. L., Richardson, A. J., Grealy, A. K., Stat, M., Bejder, L., & Bunce, M. (2017). DNA metabarcoding for diet analysis and biodiversity: A case study using the endangered Australian Sea Lion (
Neophoca cinerea). 
Ecology and Evolution, 7(14), 5435-5453. 
https://doi.org/10.1002/ece3.3123
 Castillo-Guerrero, J. A., Guevara-Medina, M. A., & Mellink, E. (2011). Breeding ecology of the Red-billed Tropicbird 
Phaethon aethereus under contrasting environmental conditions in the Gulf of California. 
Ardea, 99(1), 61-71. 
https://doi.org/10.5253/078.099.0108
 Castro-Hernández, J. J., & Santana-Ortega, A. T. (2000). 
Synopsis of biological data on the Chub Mackerel (Scomber japonicus 
Houttuyn, 1782). FAO Fisheries Synopsis No. 157. Food and Agriculture Organization of the United Nations. 
https://www.fao.org/4/x4287e/x4287e.pdf
 Cisneros, M. A., Estrada, J., & Montemayor, G. (1990). Growth, mortality and recruitment of exploited small pelagic fishes in the Gulf of California, Mexico. 
Fishbyte, 8(1), 15-17. 
https://hdl.handle.net/20.500.12348/3174
 Cisneros-Mata, M. A., Nevárez-Martínez, M. O., & Hammann, M. G. (1995). 
The rise and fall of the Pacific sardine, Sardinops sagax caeruleus 
Girard, in the Gulf of California, Mexico. 
CalCOFI Reports, 36, 136-143. 
https://calcofi.org/downloads/publications/calcofireports/v36/CalCOFI_Rpt_Vol_36_1995.pdf
 Cisneros-Montemayor, A. M., Cheung, W. W. L., & Ota, Y. (Eds.). (2019). 
Predicting future oceans: Sustainability of ocean and human systems amidst global environmental change. Elsevier Science. 
https://doi.org/10.1016/C2018-0-02416-0
 Diario Oficial de la Federación. (2002, June 13). 
Decreto por el que se declara área natural protegida con la categoría de reserva de la biosfera, la región denominada Isla San Pedro Mártir, ubicada en el Golfo de California, frente a las costas del Municipio de Hermosillo, Estado de Sonora, con una superficie total de 30,165-23-76.165 hectáreas. 
https://simec.conanp.gob.mx/pdf_decretos/25_decreto.pdf
 Diop, N., Zango, L., Beard, A., Ba, C. T., Ndiaye, P. I., Henry, L., Clingham, E., Oppel, S., & González-Solís, J. (2018). Foraging ecology of tropicbirds breeding in two contrasting marine environments in the tropical Atlantic. 
Marine Ecology Progress Series, 607, 221-236. 
https://doi.org/10.3354/meps12774
 Galaxy Community. (2022). The Galaxy platform for accessible, reproducible and collaborative biomedical analyses: 2022 update. 
Nucleic Acids Research, 50(W1), W345-W351. 
https://doi.org/10.1093/nar/gkac247
 Hammer, S., Nager, R. G., Johnson P. C. D., Furness, R. W., & Provencher, J. F. (2016). Plastic debris in Great Skua (
Stercorarius skua) pellets corresponds to seabird prey species. 
Marine Pollution Bulletin, 103(1-2), 206-210. 
https://doi.org/10.1016/j.marpolbul.2015.12.018
 Hyrenbach, K. D., Hester, M. M., Johnson, J. A., Lyday, S., Bingham, S., & Pawloski, J. (2013). First evidence of plastic ingestion by White-tailed Tropicbirds from O‘ahu, Hawai‘i. 
Marine Ornithology, 41(2), 167-169. 
http://doi.org/10.5038/2074-1235.41.2.1035
 Kibria, M. G., Masuk, N. I., Safayet, R., Nguyen, H. Q. & Mourshed, M. (2023). Plastic waste: Challenges and opportunities to mitigate pollution and effective management. 
International Journal of Environmental Research, 17, Article 20. 
https://doi.org/10.1007/s41742-023-00507-z
 Laist, D. W. (1997). Impacts of marine debris: Entanglement of marine life in marine debris including a comprehensive list of species with entanglement and ingestion records. In J. M. Coe & D. B. Rogers (Eds.), 
Marine debris: Sources, impacts, and solutions (pp. 99-139). Springer. 
https://doi.org/10.1007/978-1-4613-8486-1_10
 Leray, M., Yang, J. Y., Meyer, C. P., Mills, S. C., Agudelo, N., Ranwez, V., Boehm, J. T., & Machida, R. J. (2013). A new versatile primer set targeting a short fragment of the mitochondrial COI region for metabarcoding metazoan diversity: Application for characterizing coral reef fish gut contents. 
Frontiers in Zoology, 10, Article 34. 
https://doi.org/10.1186/1742-9994-10-34
 Lo, N. C. H., Dorval, E., Funes-Rodríguez, R., Hernández-Rivas, M. E., Huang, Y., & Fan, Z. (2010). Utilities of larval densities of Pacific Mackerel (
Scomber japonicus) off California, USA, and west coast of Mexico from 1951 to 2008, as spawning biomass indices. 
Ciencia Pesquera, 18(2), 59-75. 
https://www.gob.mx/imipas/documentos/revista-ciencia-pesquera-volumen-18-numero-2
 Louw, G. G., van der Lingen, C. D., & Gibbons, M. J. (1998). Differential feeding by Sardine 
Sardinops sagax and Anchovy 
Engraulis capensis recruits in mixed shoals. 
South African Journal of Marine Science, 19(1), 227-232. 
https://doi.org/10.2989/025776198784126647
 Madden, H., Boehm, H., & Mielke, L. (2023). Foraging ecology of Red-Billed Tropicbirds on Saba, Caribbean Netherlands, during early chick-rearing. 
Ardea, 111(2), 463-475. 
https://doi.org/10.5253/arde.2022.a14
 Madden, H., & Eggermont, E. (2020). First evidence of plastic ingestion by Red-billed Tropicbirds 
Phaethon aethereus from St. Eustatius, Caribbean Netherlands. 
Marine Ornithology, 48(2), 157-160. 
https://doi.org/10.5038/2074-1235.48.2.1366
 Madden, H., Satgé, Y., Wilkinson, B., & Jodice, P. G. R. (2022). Foraging ecology of Red-billed Tropicbird 
Phaethon aethereus in the Caribbean during early chick rearing revealed by GPS rracking. 
Marine Ornithology, 50(2), 165-175. 
https://doi.org/10.5038/2074-1235.50.2.1486
 Marcuk, V., Piña-Ortiz, A., Castillo-Guerrero, J. A., Masello, J. F., Bustamante, P., Griep, S., & Quillfeldt, P. (2024). Trophic plasticity of a tropical seabird revealed through DNA metabarcoding and stable isotope analyses. 
Marine Environmental Research, 199(July), Article 106627. 
https://doi.org/10.1016/j.marenvres.2024.106627
 Masello, J. F., Barbosa, A., Kato, A., Mattern, T., Medeiros, R., Stockdale, J. E., Kümmel, M. N., Bustamante, P., Belliure, J., Benzal, J., Colominas-Ciuró, R., Menéndez-Blázquez, J., Griep, S., Goesmann, A., Symondson, W. O. C., & Quillfeldt, P. (2021). How animals distribute themselves in space: Energy landscapes of Antarctic avian predators. 
Movement Ecology 9, Article 24. 
https://doi.org/10.1186/s40462-021-00255-9
 McInnes, J. C., Alderman, R., Lea, M.-A., Raymond, B., Deagle, B. E., Phillips, R. A., Stanworth, A., Thompson, D. R., Catry, P., Weimerskirch, H., Suazo, C. G., Gras, M., & Jarman, S. N. (2017). High occurrence of jellyfish predation by Black-browed and Campbell albatross identified by DNA metabarcoding. 
Molecular Ecology, 26(18), 4831-4845. 
https://doi.org/10.1111/mec.14245
 Navarro, A., Pérez Luzardo, O., Gómez, M., Acosta-Dacal, A., Martínez, I., de la Rosa, J. F., Macías-Montes, A., Suárez-Pérez, A., & Herrera, A. (2023). Microplastics ingestion and chemical pollutants in seabirds of Gran Canaria (Canary Islands, Spain). 
Marine Pollution Bulletin, 186(January), Article 114434. 
https://doi.org/10.1016/j.marpolbul.2022.114434
 Nevárez-Martínez, M. O., Lluch-Belda, D., Cisneros-Mata, M. A., Santos-Molina, J. P., Martínez-Zavala, M. A., & Lluch-Cota, S. E. (2001). Distribution and abundance of the Pacific Sardine (
Sardinops sagax) in the Gulf of California and their relation with the environment. 
Progress in Oceanography, 49(1-4), 565-580. 
https://doi.org/10.1016/S0079-6611(01)00041-6
 Nunes, L. S., Silva, A. G., Espínola, L. A., Blettler, M. C. M., & Simões, N. R. (2021). Intake of microplastics by commercial fish: A Bayesian approach. 
Environmental Monitoring and Assessment 193, Article 402. 
https://doi.org/10.1007/s10661-021-09156-1
 Ostle, C., Thompson, R. C., Broughton, D., Gregory, L., Wootton, M., & Johns, D. G. (2019). The rise in ocean plastics evidenced from a 60-year time series. 
Nature Communications, 10, Article 1622. 
https://doi.org/10.1038/s41467-019-09506-1
 Petry, M. V., da Silva Fonseca, V. S., & Scherer, A. L. (2007). Analysis of stomach contents from the Black-Browed Albatross, 
Thalassarche melanophris, on the coast of Rio Grande do Sul, Southern Brazil. 
Polar Biology, 30, 321-325. 
https://doi.org/10.1007/s00300-006-0186-6
 Piña-Ortiz, A., González-Zamora, D. A., Paz, J. A., Hernández-Vázquez, S., Mellink, E., Bustamante, P., Quillfeldt, P., & Castillo-Guerrero, J. A. (2024). Parental duties and foraging strategies of a tropical pelagic seabird (
Phaethon aethereus, Aves: Phaethontidae) during the breeding season. 
Marine Biology, 171, Article 64. 
https://doi.org/10.1007/s00227-023-04375-1
 Piña-Ortiz, A., Hernández-Vázquez, S., Fernández, G., & Castillo-Guerrero, J. A. (2018). Distribution and population size of the Red-billed Tropicbird (
Phaethon aethereus) in Mexico. 
Waterbirds, 41(2), 135-144. 
https://doi.org/10.1675/063.041.0204
 Provencher, J. F., Bond, A. L., Avery-Gomm, S., Borrelle, S. B., Bravo Rebolledo, E. L., Hammer, S., Kühn, S., Lavers, J. L., Mallory, M. L., Trevail, A., & van Franeker, J. A. (2017). Quantifying ingested debris in marine megafauna: A review and recommendations for standardization. 
Analytical Methods, 2017(9), 1454-1469. 
https://doi.org/10.1039/C6AY02419J
 R Core Team. (2023). 
R (version 4.3.1) [Computer software]. The R Foundation for Statistical Computing. 
https://www.r-project.org/
 Rapp, D. C., Youngren, S. M., Hartzell, P., & Hyrenbach, K. D. (2017). Community-wide patterns of plastic ingestion in seabirds breeding at French Frigate Shoals, Northwestern Hawaiian Islands. 
Marine Pollution Bulletin, 123(1-2), 269-278. 
https://doi.org/10.1016/j.marpolbul.2017.08.047
 Robards, M. D. (1993). Plastic ingestion by North Pacific seabirds. Report NOAA-43ABNF203014. US Department of Commerce.
 
      
        
      
        
      
        Ryan, P. G. (2016). Ingestion of plastics by marine organisms. In H. Takada & H. K. Karapanagioti (Eds.), 
Hazardous chemicals associated with plastics in the marine environment (pp. 235-266). Springer Cham. 
https://doi.org/10.1007/698_2016_21
 Schmaltz, E., Melvin, E. C., Diana, Z., Gunady, E. F., Rittschof, D., Somarelli, J. A., Virdin, J., Dunphy-Daly, M. M. (2020). Plastic pollution solutions: Emerging technologies to prevent and collect marine plastic pollution. 
Environment International, 144(November), Article 106067. 
https://doi.org/10.1016/j.envint.2020.106067
 Schuyler, Q., Hardesty, B. D., Wilcox, C., & Townsend, K. (2014). Global analysis of anthropogenic debris ingestion by sea turtles. 
Conservation Biology, 28(1), 129-139. 
https://doi.org/10.1111/cobi.12126
 Schwartzkopf, B. D., Dorval, E., James, K. C., Walker, J. M., Snodgrass, O. E., Porzio, D. L., & Erisman, B. E. (2022). 
A summary report of life history information on the central subpopulation of Northern Anchovy (Engraulis mordax
) for the 2021 stock assessment. NOAA Technical Memorandum NMFS-SWFSC-659. Southwest Fisheries Science Center, National Oceanic and Atmospheric Administration. 
https://doi.org/10.25923/ckvg-va49
 Sileo, L., Sievert, P. R., Samuel, M. D., & Fefer, S. I. (1990). Prevalence and characteristics of plastic ingested by Hawaiian seabirds. In R. S. Shomura & M. L. Godfrey (Eds.), Proceedings of the 2nd International Conference on Marine Debris, 02-07 April 1989, Honolulu, Hawai‘i (pp. 665-681). NOAA Technical Memorandum NOAA-TM-NMFS-SWFSC-154. US Department of Commerce, National Oceanic and Atmospheric Administration.
 
      
        Sindermann, C. J. (Ed.). (1995). Ocean pollution: Effects on living resources and humans. CRC Press.
 
      
        Spear, L. B., Ainley, D. G., & Ribic, C. A. (1995). Incidence of plastic in seabirds from the tropical Pacific, 1984-91: Relation with distribution of species, sex, age, season, year and body weight. 
Marine Environmental Research, 40(2), 123-146. 
https://doi.org/10.1016/0141-1136(94)00140-K
 Su, L., Xiong, X., Zhang, Y., Wu, C., Xu, X., Sun, C., & Shi, H. (2022). Global transportation of plastics and microplastics: A critical review of pathways and influences. 
Science of the Total Environment, 831(July), Article 154884. 
https://doi.org/10.1016/j.scitotenv.2022.154884
 Tokunaga, Y., Okochi, H., Tani, Y., Niida, Y., Tachibana, T., Saigawa, K., Katayama, K., Moriguchi, S., Kato, T., & Hayama, S. (2023). Airborne microplastics detected in the lungs of wild birds in Japan. 
Chemosphere, 321(April), Article 138032. 
https://doi.org/10.1016/j.chemosphere.2023.138032
 Vandenabeele, S. P., Shepard, E. L., Grogan, A. & Wilson, R. P. (2012). When three per cent may not be three per cent: Device-equipped seabirds experience variable fight constraints. 
Marine Biology, 159, 1-14. 
https://doi.org/10.1007/s00227-011-1784-6
 van der Lingen, C. D. (1994). Effect of particle size and concentration on the feeding behaviour of adult pilchard 
Sardinops sagax. Marine Ecology Progress Series, 109(1), 1-13. 
https://doi.org/10.3354/meps109001
 van Franeker, J. A., & Meijboom, A. (2002). 
LITTER NSV: Marine litter monitoring by Northern Fulmars (A pilot study). Alterra-rapport No. 401. Alterra. 
https://edepot.wur.nl/45695
 Velarde, E., Ezcurra, E., & Anderson, D. W. (2013). Seabird diets provide early warning of sardine fishery declines in the Gulf of California. 
Scientific Reports 3, Article 1332. 
https://doi.org/10.1038/srep01332
 Vesterinen, E. J., Lilley, T., Laine, V. N., & Wahlberg, N. (2013). Next generation sequencing of fecal DNA reveals the dietary diversity of the widespread insectivorous predator Daubenton's Bat (
Myotis daubentonii) in southwestern Finland. 
PLoS ONE, 8(11), Article e82168. 
https://doi.org/10.1371/journal.pone.0082168
 Waap, S. (2015). 
Trophic relationships among pelagic predators of the deep seas of the Madeira islands [Doctoral dissertation, Cardiff University]. Online Research @ Cardiff. 
https://orca.cardiff.ac.uk/id/eprint/75359/
 Wang, G.-X., Huang, D., Ji, J.-H., Völker, C., & Wurm, F. R. (2021). Seawater-degradable polymers—fighting the marine plastic pollution. 
Advanced Science, 8(1), Article 2001121. 
https://doi.org/10.1002/advs.202001121
 Wayman, C., Fernández-Piñas, F., Fernández-Valeriano, R., García-Baquero, G. A., López-Márquez, I., González-González, F., Rosal, R., & González-Pleiter, M. (2024). The potential use of birds as bioindicators of suspended atmospheric microplastics and artificial fibers. 
Ecotoxicology and Environmental Safety, 282(September), Article 116744. 
https://doi.org/10.1016/j.ecoenv.2024.116744
 Willis, K. A., Serra-Gonçalves, C., Richardson, K., Schuyler, Q. A., Pedersen, H., Anderson, K., Stark, J. S., Vince, J., Hardesty, B. D., Wilcox, C., Nowak, B. F., Lavers, J. L., Semmens, J. M., Greeno, D., MacLeod, C., Frederiksen, N. P. O., & Puskic, P. S. (2022). Cleaner seas: Reducing marine pollution. 
Reviews in Fish Biology and Fisheries, 32, 145-160. 
https://doi.org/10.1007/s11160-021-09674-8
 Yorio, P., Marinao, C., Kasinsky, T., Ibarra, C., & Suárez, N. (2020). Patterns of plastic ingestion in Kelp Gull (
Larus dominicanus) populations breeding in northern Patagonia, Argentina. 
Marine Pollution Bulletin, 156(July), 111240. 
https://doi.org/10.1016/j.marpolbul.2020.111240
 Young, M. J., Dutoit, L., Robertson, F., van Heezik, Y., Seddon, P. J., & Robertson, B. C. (2020). Species in the faeces: DNA metabarcoding as a method to determine the diet of the endangered Yellow-eyed Penguin. 
Wildlife Research, 47(6), 509-522. 
https://doi.org/10.1071/WR19246