What is the meaning of Mary poem called Flare?

"Flare" by Mary Oliver describes the speaker observing a red bird perched on a bare limb while reflecting on life and life's endings. In her poem, life and death go hand in hand:

* She describes the "flare of life" burning out as the poem opens but says it's an end to fear it as an inevitability, like the coming of the evening light at dusk.

* As the poem ends, Oliver reflects on those who had lives ending in despair but now rest "under the sun".