Denver City Park Lakes

Background | Criteria | Northwest Colorado | Northeast Colorado
Southwest Colorado | Southeast Colorado

Denver City Park Lakes
Denver County

Size: 24 surface-acres (Ferrill Lake)

5.5 surface-acres (Duck Lake)

~.75-1.5 acres (islands)

Elevation: 5280 feet

Habitats: Primary – open water

Secondary – island with trees

Ownership: Municipal (City of Denver)

Land Use: Primary – recreation/tourism, water supply

IBA Criterion: 4 (heronries)

Site description

Location:
The two lakes (Ferrill and Duck) which comprise this site are located within Denver City Park, in east Denver. The Denver Zoo lies north of Duck Lake, while the Denver Museum of Nature and Science is one-half mile northeast of Ferrill Lake.

Vegetative/natural features:
Ferrill and Duck Lakes are man-made lakes, each with a treed island in the center.

Ornithological Importance

Ferrill Lake has, and Duck Lake has or has had, a closely-packed colony of Black-crowned Night Herons and Double-crested Cormorants. The colony of night herons probably has more nests than any in Colorado.

Breeding species:	Average #	Maximum #
Black-crowned Night Heron	100 pairs	150 pairs
Double-crested Cormorant	50 pairs	100 pairs
Yellow-crowned Night Heron		1 pair

Conservation/Management Issues

Minor threats:
1. introduced animals (Canada geese);
2. pollution from the heron colony;
3. disturbance to birds and habitat from heavy recreational use of City Park.

Management details:
While City Park permits paddle-boats and canoes on Ferrill Lake, they do not permit motorized boats. Water is supplied to Ferrill Lake through the City Ditch from the South Platte River from May through October. Park managers use this water as irrigation to water the park grounds. The water level drops dramatically during the off-season (November through April). Ferrill Lake will likely be completely drained in 2001 to fix the electric fountain located in its center.