A Phillips 3000 ultrasound unit was modified for near-pool usage by adding an extendable dental arm to allow the ultrasonographer to scan Killer whales in lateral and ventral positions. A 1.5 megahertz sector transducer was assembled by the Phillips Corporation as a standard scanner for usage. Electronically the monitor field was modified to allow visualization of deeper tissues normally not available to the sonographer. Two Killer whales were monitored at various pregnancy stages to gauge the limitations of this modality. Partial fetal visualization is possible even in the last trimester which may allow fetal heart monitoring as well as body position.