From the article:

A recent quiet morning at a Florida marine research facility was interrupted by tapping at the back door.

A biologist walked over to investigate and found a brown pelican standing on the stoop and pecking at the glass with its long beak. It stood there patiently, as if waiting for help. A quick inspection revealed the pelican was injured.

Fishing line was wrapped around the pelican’s right wing, and a double-barbed treble hook was stuck in the wing, restricting the bird’s ability to fly. About a dozen cactus spines were lodged in its left foot.

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Hilton, 26, said she had never treated a pelican before but relied on techniques she uses while inserting tags into smalltooth sawfish, the fish she primarily studies. The pelican was calm throughout the procedure, which Hilton said took about five minutes but felt like an hour because of the unusual nature of the situation.

Her co-worker then carried the pelican to the basin, where the bird stretched and flapped its wings for a few minutes before flying away.

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Some scientists have theories as to why the bird knew who to ask for help. Gerald Hough, a professor who studies bird behavior at Rowan University in New Jersey, said the pelican might have previously seen researchers carrying fish in and out of the facility. In its desperation, Hough said, the pelican might have visited in hopes of finding food.

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Pelicans associate people and docks with food, Hough said, so when they’re hungry, they sometimes spend time near people.

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Young pelicans are often less fearful of people than their elders who might have been chased or hurt by humans, said Juliet Lamb, a marine scientist who studies seabirds. The pelican at NOAA’s lab appeared to be born this past spring or summer due to its brown plumage, Lamb said.

Even if the pelican was looking for people, how did the bird know to peck at the glass door? Hough said the pelican might have confused its reflection with another pelican that the bird was trying to engage with. Plus, the pelican might have stood near the door to escape the sun, Hough said.