[5] The diet of the southern brook lamprey changes as it undergoes metamorphosis during its life cycle from one phase to the next.

[6] After metamorphosis into the adult phase, southern brook lampreys do not feed but rely on stored fat reserves accumulated during the larval stage for energy and nutrients.

[8] Southern brook lampreys in the larval stage serve as prey for a wide range of fish and bird species.

The southern brook lamprey shares similar habitats and resources with many species of shiners (Notropis), the longnose dace (Rhinichthys cataractae), Johnny darters (Etheostoma nigrum), and mottled sculpins (Cottus bairdi).

During the larval stage, the southern brook lamprey inhabits a distinct micro habitat involving relatively slow moving water and a sandy substrate.

Adults are found in crevices and cracks between large rocks in deeper, faster moving water than the habitat occupied during the larval stage.

[11] Spawning usually occurs between April and May and takes place in another distinct microhabitat consisting of shallow riffle areas with rocky substrate with a water temperature falling between 17 °C to 21 °C.

[12] No evidence of biological factors has been found that would contribute to a decline in the abundance or the range of the creature; in fact, the biggest threat to the lamprey and closely related species is human-induced alteration of suitable microhabitats.