Wild hyacinth (Camassia scilloides) COSEWIC assessment and status report: chapter 11

Range of Occurrence in Canada:

Ontario, Lake Erie islands only

Extent of occurrence (EO) (km²) :

4.5 km²

specify trend (decline, stable, increasing, unknown) :

Stable, but some habitats not secure

are there extreme fluctuations in EO (> 1 order of magnitude)?

No

Area of occupancy (AO) (km²) :

1.1 km²

specify trend (decline, stable, increasing, unknown) :

Stable, but some popula-tions lost, others not secure.

are there extreme fluctuations in AO (> 1 order magnitude)?

No.

Number of extant locations :

6

specify trend in # locations (decline, stable, increasing, unknown) :

1 complete loss, 1severe decline, others stable.

are there extreme fluctuations in # locations (>1 order of magnitude)?

No.

Habitat trend: 
specify declining, stable, increasing or unknown trend in area, extent or quality of habitat :

Currently stable, but private land not  secure.

Generation time (average age of parents in the population) (indicate years, months, days, etc.) :

Likely 2-4 years.

Number of mature individuals (capable of reproduction) in the Canadian population (or, specify a range of plausible values) :

21,200

Total population trend: 

specify declining, stable, increasing or unknown trend in number of mature individuals :

Slight increase, but may represent more intensive survey.

if decline, % decline over the last/next 10 years or 3 generations, whichever is greater (or specify if for shorter time period) :

Decline in 2 populations in 13 years: one to 0%, the other to 15%.

are there extreme fluctuations in number of mature individuals (> 1 order of magnitude)?

Individuals long-lived and populations mostly stable.

Is the total population severely fragmented (most individuals found within small and relatively isolated (geographically or otherwise) populations between which there is little exchange, i.e., < 1 successful migrant / year)?

Total  population fragmented between different islands.  Some movement within large sites.

list each population and the number of mature individuals in each :

1. Fish Point (Pelee Island): 2090
2. Stone Road Alvar (Pelee Island): 4485
3. Middle Point (Pelee Island): 4860
4. Middle Island: 865
5. Middle Sister Island: 3230
6. Hen Island: 5680
7. East Sister Island: 0

specify trend in number of populations (decline, stable, increasing, unknown)

• 1 lost, 1 severe decine,
• 5 stable

are there extreme fluctuations in number of populations (>1 order of magnitude)?

Other than 1 lost and one severe decline, no.

does species exist elsewhere (in Canada or outside)?

Canada: no.  USA, yes.

status of the outside population(s)?

In the USA, S1 in 3 states, S2 in 6, none S4 or S5.

is immigration known or possible?

Very unlikely.

would immigrants be adapted to survive here?

Likely if from northern source.

is there sufficient habitat for immigrants here?

Secure habitat is occupied; problem is loss or degradation of habitat.