Pine Siskin (Spinus pinus; siskin) and Lawrence’s Goldfinch (Spinus lawrencei; Lawrence’s) have many biological and ecological aspects unknown, including longevity, survivorship, site fidelity, nesting site selection, migration routes, and preferred overwintering areas. In 2023, a targeted banding and resighting study began at an urban residence in San Diego County that has attracted record numbers of Lawrence’s and siskins for over 13 years in an attempt to address the lack of data on these species. Over 200 Lawrence’s and twelve siskins have been banded, and in late Spring/early Summer 2025, two juveniles, two adult siskins (one a resight), and a juvenile Lawrence's were observed there. The siskin resighting marks an unprecedented observation on the coastal slope at this elevation and creates more origin and site fidelity questions. There are no site fidelity records for Lawrence’s at any time of the year anywhere in their range, except at this property, which now holds several U.S. banding records for Lawrence's, at least. Continued banding and data collection at this location is critical to attempt to better understand both species’ biology, longevity, survivorship, breeding, migration routes, and overwintering areas, which may also help understand the impacts of climate change on nomadic avian species.

A birder and a conservationist at a young age in her home state of Pennsylvania, Emily Mastrelli worked to become a Master Bander, chasing her dream of holding birds. Emily's obsession with banding has taken her to as far as Maine to band Nelson’s Sparrows and Red-winged Blackbirds, to the cliffs of the Mojave to band prairie falcon nestlings, to the open sands of SD County to band California Least Terns, to the hills of Camp Pendleton to band coastal California Gnatcatchers, and to Joshua Tree NP, San Felipe Valley, Riverside and Orange Counties, and Tijuana Slough National Wildlife Refuge.