Enough
Biblical echo
God distributes bread like the parable of talents—unequal portions. The bird gets a loaf, she gets a crumb, setting up the poem's paradox about scarcity.
Starvation economics
She won't consume what she has. The crumb becomes more valuable as possession than as food—a reversal of normal hunger logic.
Colonial wealth
An Indiaman is a merchant ship trading with India—massive commercial wealth. She's contrasting imperial riches with her single crumb.
Paradox completed
Final inversion: poverty becomes sovereignty. The one with least claims to rule over those with most.