Lichens

Lichen communities living on rock.

Grand Canyon National Park

There is a great deal of exposed rock in and around the Grand Canyon. Much of of that rock is covered by lichens.

A lichen is what one could call a simple biological “community” because it is made up of at least two mutually-dependent organisms. In a lichen, some type of fungi is found along with green algae and /or cyanobacteria.

 

A lichen community is therefore stronger than either fungus or algae alone. Here's how they help each other out; the green algae uses the photosynthesis process to produce food for the fungus, while the fungus protects the algae from the elements and extracts nutrients from the rocks and soil.

Lichens usually colonize north-facing surfaces since exposure to the sun's heat and radiation is less on north-facing rocks and slopes. Lichens may also grow on healthy, mature cryptobiotic soil crust, and occasionally on live or dead plant material. Many species of lichen are found within Grand Canyon National Park.

Lichens are well adapted to arid climates since they can produce food at any temperature above freezing. Another thing that makes lichens good desert survivors is that they can soak up more than their weight in water. Fungi and green algae are non-vasular plants (without roots and stems) so they can directly soak up dew and rain into their cells.

 

 

×

Species Attribute Definitions

Definitions

Occurrence

Occurrence values are defined below. One or more Occurrence Tags may be associated with each Occurrence value.

Present: Species occurs in park; current, reliable evidence available.

Probably Present: High confidence species occurs in park but current, verified evidence needed.

Unconfirmed: Species is attributed to park but evidence is weak or absent.

Not In Park: Species is not known to occur in park.

---

Occurrence Tags

Adjacent: Species is known to occur in areas near to or contiguous with park boundaries.

False Report: Species was reported to occur within the park, but current evidence indicates the report was based on misidentification, a taxonomic concept no longer accepted, or other similar problem of error or interpretation.

Historical: Species' historical occurrence in park is documented. Assigned based on judgment as opposed to determination based on age of the most recent evidence.

---

Abundance

Abundant:

• Animals: May be seen daily, in suitable habitat and season, and counted in relatively large numbers.
• Plants: Large number of individuals; wide ecological amplitude or occurring in habitats covering a large portion of the park.

Common:

• Animals: May be seen daily, in suitable habitat and season, but not in large numbers.
• Plants: Large numbers of individuals predictably occurring in commonly encountered habitats but not those covering a large portion of the park.

Uncommon:

• Animals: Likely to be seen monthly in appropriate habitat and season. May be locally common.
• Plants: Few to moderate numbers of individuals; occurring either sporadically in commonly encountered habitats or in uncommon habitats.

Rare:

• Animals: Present, but usually seen only a few times each year.
• Plants: Few individuals, usually restricted to small areas of rare habitat.

Occasional:

• Animals: Occurs in the park at least once every few years, varying in numbers, but not necessarily every year.
• Plants: Abundance variable from year to year (e.g., desert plants).

Unknown: Abundance unknown

---

Nativeness

Native: Species naturally occurs in park or region.

Non-native: Species occurs on park lands as a result of deliberate or accidental human activities.

Unknown: Nativeness status is unknown or ambiguous.

×

List Differences

The Checklist contains only those species that are designated as "present" or "probably present" in the park.

The Full List includes all the checklist species in addition to species that are unconfirmed, historically detected, or incorrectly reported as being found in the park. The full list also contains species that are "in review" because their status in the park hasn't been fully determined. Additional details about the status of each species is included in the full list.

The checklist will almost always contain fewer species than the full list.

Select a Park:

Grand Canyon National Park

Select a Species Category (optional):

All Amphibians Birds Fish Mammals Reptiles Vascular Plants

Get Checklist Get Full List List Differences

Species attribute definitions

Search results will be displayed here.

Visit NPSpecies for more comprehensive information and advanced search capability. Have a suggestion or comment on this list? Let us know.