What is a summary of the poem "The Mother Bird" by Walter de la Mare?

Here's a quick summary: In "The Mother Bird" by Walter de la Mare, the speaker of the poem peeks into a hedge and sees a mother bird in her nest. The bird sees the speaker and seems to react bravely, uttering one single, sharp tweet. When she makes this one sound, it's not a "chirp" or a "trill" (which are sweet little sounds) but rather a "passionate note of victory," as if the bird is sure her sound will scare away this giant human invader. At this, the speaker slips away, smiling, to leave the bird alone.

Here's a little more information about what's going on in the poem. "The Mother Bird" is full of contradictions. Throughout the poem, the speaker characterizes the mother bird as having a mixture of meekness and valiance: the bird is "brave" as she looks at the speaker, yet has "beseeching" eyes that look at him "meekly." More contradictions attributed to the bird include "valiant tears" and "hopeless joy," as if the animal has the human-like ability to experience complex and contradictory emotions: fearlessness and fearfulness, hope and hopelessness. As the poem comes to a close, the speaker labels the bird a "mother" but points out her "lonely" state in the nest--we assume the baby birds haven't hatched yet, so she's not really a mother, then. The speaker's reaction to the bird's sudden cry is a final contradiction in the poem; that is, while he's making his exit because the bird so effectively and victoriously drove him out of the hedge with her "sharp solitary note," he's also slipping away with a foolish smile on his face, as if he were the victor in this situation.

Finally, let's look at how you might break the poem into sections in case you needed to create a more detailed summary. The entire poem is one long sentence in eighteen lines, punctuated with commas, colons, and semicolons. The two colons in the poem both introduce new independent clauses, so they could be interpreted as periods if you needed to break the lines of the poem into smaller units of meaning. In that case, the first three lines are like a sentence unto themselves that establishes the exposition of the poem's story:

Through the green twilight of a hedge
I peered, with cheek on the cool leaves pressed,
And spied a bird upon a nest:

The next eleven lines make up the middle "sentence" of the poem and contain the rising action and climax of the poem:

Two eyes she had beseeching me
Meekly and brave, and her brown breast
Throbb'd hot and quick above her heart;
And then she oped her dagger bill, - 
'Twas not a chirp, as sparrows pipe
At break of day; 'twas not a trill,
As falters through the quiet even;
But one sharp solitary note,
One desperate, fierce, and vivid cry
Of valiant tears, and hopeless joy,
One passionate note of victory:

The final four lines present the falling action and resolution, showing how the speaker retreats from the hedge and offers one final description of the mother bird:

Off, like a fool afraid, I sneaked,
Smiling the smile the fool smiles best,
At the mother bird in the secret hedge
Patient upon her lonely nest.