Death of a Darwin's Finch: a consequence of human-made debris?

Urban living influences the nesting success of Darwin’s finches in the Galápagos Islands

“…Debris-related mortalities documented in the study were all due to ingestion/entanglement with anthropogenic debris that was found incorporated into the nest. Other studies have observed mortalities due to both entanglement and ingestion of anthropogenic debris in nestling and adult land birds (Henry et al, 2011;Mee et al, 2007;Theodosopoulos & Gotanda, 2019).…”

“…Because urban areas are supplemented with additional human food resources (De León et al., 2018), finch reproductive effort and success is predicted to increase in urban areas compared to nonurban areas. However, finches incorporate human‐related debris into their nest (Knutie et al., 2014; Theodosopoulos & Gotanda, 2019). Debris can include plastic, fishing line, human hair, synthetic string, paper, etc.…”

“…Debris can include plastic, fishing line, human hair, synthetic string, paper, etc. which are readily available in many urban areas and can result in injury (Jiguet et al, 2019) or even death due to entanglement (Jagiello et al., 2018; Theodosopoulos & Gotanda, 2019; Townsend & Barker, 2014). Therefore, although urban finches are predicted to have higher overall reproductive success, urban finches likely face a trade‐off related to anthropogenic debris in their nests: urban finches may benefit from urban resource availability but may also suffer negative consequences (i.e., entanglement, ingestion) due to anthropogenic debris use.…”

Urban living influences the reproductive success of Darwin’s finches in the Galápagos Islands

“…Furthermore, 24% of urban nests were associated with debris-related mortalities and the proportion of anthropogenic debris comprising the total nest mass impacted nestling survival. Other studies have observed mortalities due to both entanglement and ingestion of anthropogenic debris in nestling and adult land birds (Mee et al, 2007;Henry, Wey, & Balança, 2011;Theodosopoulos & Gotanda, 2019). However, few studies have examined the effect of debris on reproductive success in land birds (Jagiello et al, 2018) and only one previous study has examined passerines (Townsend & Barker, 2014).…”

“…Second, because finches will incorporate human-related material into their nest (Knutie et al, 2014;Theodosopoulos & Gotanda, 2019), we predicted that urban birds would incorporate more anthropogenic debris into their nests than non-urban birds. Because anthropogenic debris can cause mortality in birds (Townsend & Barker, 2014;Jagiello et al, 2018;Jiguet et al, 2019, Theodosopoulos & Gotanda, 2019, we predicted that debris would result directly in mortalities of urban birds (via ingestion or entanglements).…”