A beached, juvenile California sea lion (Zalophus californianus) was found to be in severe respiratory failure.

Radiographs, blood, sputum and fecal exams confirmed the diagnosis of Parafilaroides decorus with a diffuse secondary bacterial pneumonia.

Inhalation therapy with bronchodilators and mucolytic agents combined with antibiotics and anthelmintics will be discussed; serial radiographs taken during rehabilitation will be presented.