Shumard oak (Quercus shumardii) COSEWIC update status report: chapter 12

Technical Summary

Quercus shumardii

Shumard Oak – chêne de Shumard

Range of Occurrence in Canada:

Ontario

Extent and Area information

extent of occurrence (EO) (km²)

>5000

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

stable

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

no

area of occupancy (AO) (km²) :

perhaps <50

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

stable?

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

no

number of extant locations

<40

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

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 :

possibly slight decline in habitat availability

Population information

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

Unknown
(production of acorns may not begin until trees are >25 years old)

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

<<1000 and likely fewer than 250

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

perhaps stable

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

 

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

no

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)?

no but localities are clumped in two main regions of southwestern Ontario

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

no precise figures are available

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

perhaps stable with new trees located due to increased search effort

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

no

Threats

inadvertent loss from roadside brushing of shrubbery and lack of recognition of distinctness from red oak

Rescue Effect (immigration from an outside source)

Low (Canadian occurrences are somewhat disjunct from the main range in the USA)

does species exist elsewhere (in Canada or outside)?

USA

status of the outside population(s)?

widespread in south-central USA

is immigration known or possible?

not likely

would immigrants be adapted to survive here?

yes

is there sufficient habitat for immigrants here?

yes

Quantitative Analysis

Page details

Date modified: