Scientific Name: Danaus plexippus
Taxonomy Group: Arthropods
COSEWIC Range: British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, Quebec, New Brunswick, Prince Edward Island, Nova Scotia
COSEWIC Assessment Date and Status Change: November 2016
COSEWIC Status: Endangered
COSEWIC Status Criteria: A2bce
COSEWIC Reason for Designation: This large showy species is one of the most well-known butterflies in the world. The Canadian population is migratory with two distinct pathways and cumulative threats at both overwintering sites and along the long migratory routes. The migratory group west of the Rocky Mountains moves between coastal California and southern British Columbia. The group east of the Rocky Mountains represents the vast majority of the Canadian population and moves between the Oyamel Forest of central Mexico and southern Canada east of Alberta. The overwintering sites in central Mexico are extremely small, and threats to these areas include illegal logging and agricultural development, and increased frequency and severity of storms during key congregation times. Declines of greater than 50% have occurred over the past decade.
COSEWIC History of Status Designation: Designated Special Concern in April 1997. Status re-examined and confirmed in November 2001 and in April 2010. Status re-examined and designated Endangered in November 2016.
SARA Status: Schedule 1, Special Concern
Date of Listing (yyyy-mm-dd): 2003-06-05
Butterfly enthusiasts and citizen scientists are encouraged to submit their Monarch observations using eButterfly. This website allows users to track their butterfly sightings and locations, organize, store and share photos, and make a valuable contribution to science and conservation.
Please note that this information is provided for general information purposes only. For the most up to date and accurate list of species listed under the Species at Risk Act, please see the Justice Laws Website.
Image of Monarch
The Monarch is a conservation icon and one of the most well-known and well-studied butterflies in the world. The species has four life stages. The adult Monarch is a large (wingspan 93 – 105 mm), showy butterfly with predominantly orange wings outlined by a broad black border and two rows of circular white spots. The caterpillar is distinctively white, yellow, and black-banded, with a pair of black filaments at its head and tail. The chrysalis is green and gold. The eggs are approximately 1 mm long, oval with a flat base and bluntly pointed apex. The Monarch is one of a few butterflies that migrate and their migration from southern Canada to Mexico has been described as an endangered biological phenomenon. The Monarch is used in classrooms all over North America to teach children about biology, metamorphosis, conservation, and an appreciation for nature. (Updated: 2018/01/19)
Blurb asking people to submit their observations through eButterfly.
Distribution and Population
The Monarch is a migratory butterfly. The overall native range of the Monarch occurs from Central America northward through the continental United States to southern Canada, and from the Atlantic Coast westward to the Pacific Coast. The Canadian range of occurrence includes portions of all ten provinces and the Northwest Territories. Monarchs are loosely divided into eastern and western subgroups based on their migratory routes and overwintering sites. Eastern Monarchs breed from Alberta east to Nova Scotia and migrate south to overwinter in the mountains of Central Mexico. Western Monarchs breed in southern British Columbia and migrate south to overwinter in coastal California. The breeding range in Canada is south of the 50° latitude in Ontario, Quebec and the Maritimes and extends north to the 54° latitude in Manitoba, Saskatchewan and Alberta. The Monarch is being assessed as one designatable unit in Canada. There is some exchange of individuals between the eastern and western migratory routes and no genetic or morphological evidence to suggest two subspecies. Monarchs have also colonized continental Europe, North Africa, Australia and many Pacific islands within the last 200 years but these colonized populations do not migrate. Population size estimates are not available for Monarchs in Canada. Each fall hundreds of thousands of Monarchs migrate through Long Point in southern Ontario but it’s unknown what proportion of the Canadian population these individuals represent. Population estimates are available for the overwintering sites, which include Monarchs from both Canada and the United States. The total overwintering population size in Mexico (eastern Monarch) was estimated at 66 million individuals in 2014-2015 and 200 million in 2015-2016. A storm in March 2016 killed a large but unknown number of Monarchs at the eastern overwintering sites. Fewer than 500,000 Monarchs currently overwinter in California (western Monarch), and only a tiny percentage of these breed in Canada. In some years, the western Canadian breeding population (in British Columbia) is so small as to be undetectable. The overwintering population in Mexico, as measured by area of occupied habitat (hectares), declined significantly over the period 1994-2015. A log-linear regression of the time series indicates an 83% decline. The 2012-2014 estimates were the lowest in the time series. The area of occupied habitat in 2015 (4 ha) was higher than the previous three years but below the time series average of 6 ha. The decline rate of the occupied habitat over a 10-year period was calculated using the slope of a log-linear regression of the entire time series applied to a period of 10 years. The estimated 10-year change was estimated to be -59%. A long-term migration monitoring study at Long Point, Ontario showed modest declines when numbers were adjusted for weather effects but similar studies at Cape May (New Jersey) and the Peninsula Point (Michigan) showed no evidence of decline. (Updated: 2018/01/19)
Milkweeds (numerous species)are the sole food plant for Monarch caterpillars. These plants grow predominantly in open and periodically disturbed habitats such as roadsides, fields, wetlands, prairies, and open forests. Milkweeds are often planted outside their native range, and sometimes wayward Monarchs are observed at these patches. Overwintering Monarchs require a cool, humid microclimate that is protected from frost, excessive sunlight, wind, and heavy precipitation. These conditions are found along the Pacific coast of California and the high elevation forests of central Mexico. Eastern Monarchs overwinter at elevations of 2900 - 3300 m in the Oyamel Fir forests in Mexico. Western Monarchs overwinter within a few kilometres of the Pacific coast of California, mainly in stands of non-native eucalyptus trees that replaced native pines starting in the 1850s, which were planted to replace native tree species. Monarchs require staging areas which are used to rest, feed, and avoid inclement weather during migration. In Canada, they are found along the north shores of the Great Lakes where Monarchs roost in trees before crossing large areas of open water. (Updated: 2018/01/19)
Adults mate during the winter or early spring at the overwintering sites in Mexico or California and begin flying north in late February or early March. About 10% of eastern Monarchs arriving in Canada fly the entire journey but most females that leave the overwintering sites breed in the southern United States. Female Monarchs lay 300 - 400 eggs singly on the undersides of milkweed leaves. The eggs hatch in three to eight days and the caterpillars feed almost continuously as they increase their body weight 2000-fold. After 9 - 14 days of feeding, the caterpillar transforms into a chrysalis and the adult emerges 9 - 15 days later. Adults of the following generations continue the migration north, many of which breed, reproduce and complete another generation in the central United States. Most Monarchs that reach Canada are the great-grandchildren of those that left Mexico. Monarchs in southern Ontario and Quebec produce two to three generations between June and October each year. Monarchs in southern British Columbia produce at least one generation each summer. Summer adults live for two to five weeks, but overwintering adults live up to nine months. The late summer adults migrate south to Mexico or California, where they overwinter and the yearly migration begins again. Monarch caterpillars sequester the chemicals present in milkweed plants, which make them, as well as adult butterflies, unpalatable to most birds and other vertebrates. (Updated: 2018/01/19)
Most North American Monarchs are concentrated in a few hectares in the winter and are vulnerable to extreme weather events, fire, diseases, predation, and anthropogenic threats. Overwintering habitat in Oyamel Fir forest in Mexico has been fragmented and degraded by conversion to agriculture, fire, logging, and forest thinning. These practices increase the exposure of overwintering Monarchs to winter storms, cold temperatures and wet conditions, resulting in increased mortality. Climate change models predict that the area of suitable forest at the overwintering sites in Mexico will decline and the frequency of winter storms will increase resulting in catastrophic mortality of Monarchs. Degradation to the western Monarch overwintering habitat is caused mainly by real estate development along the California coast and by elimination of introduced eucalyptus upon which the butterflies overwinter. The increased use of herbicides and subsequent decline in milkweeds is a significant threat facing Monarchs throughout their North American range. Increased herbicide use may also cause declines in nectar supplies needed by migrating Monarchs and reduce overwinter survival. Neonicotinoid pesticides are an emerging threat, the magnitude of which is poorly understood. (Updated: 2018/01/19)
The Monarch is protected under the federal Species at Risk Act (SARA). More information about SARA, including how it protects individual species, is available in the Species at Risk Act: A Guide.
Provincial and Territorial Protection
Recovery Progress and Activities
Butterfly enthusiasts and citizen scientists are encouraged to submit their Monarch observations using eButterfly (http://www.ipapillon.ca/#/). This website allows users to track their butterfly sightings and locations, organize, store and share photos, and make a valuable contribution to science and conservation.
Hinterland Who's Who: Monarch: http://www.hww.ca/hww2.asp?id=34
PLEASE NOTE: Not all COSEWIC reports are currently available on the SARA Public Registry. Most of the reports not yet available are status reports for species assessed by COSEWIC prior to May 2002. Other COSEWIC reports not yet available may include those species assessed as Extinct, Data Deficient or Not at Risk. In the meantime, they are available on request from the COSEWIC Secretariat.
18 record(s) found.
- COSEWIC Status Reports (1 record(s) found.)
- COSEWIC Assessments (1 record(s) found.)
- Response Statements (2 record(s) found.)
- Action Plans (8 record(s) found.)
- Management Plans (1 record(s) found.)
- COSEWIC Annual Reports (2 record(s) found.)
- Consultation Documents (2 record(s) found.)
- Recovery Document Posting Plans (1 record(s) found.)
COSEWIC Status Reports
Response Statement - Monarch (2010-12-02)This species has a population of millions to over one billion individuals. The most sensitive stage of its annual cycle is overwintering. There are two main overwintering areas: the Oyamel Fir forests of Central Mexico, where 90% of the population overwinters, and coastal regions of California. The overall area of these sites is relatively small, and threats, especially from logging in the Oyamel Fir forests, are sufficient to suggest that the species could become Threatened in the near future.
Response Statement - Monarch (2018-01-18)This large showy species is one of the most well-known butterflies in the world. The Canadian population is migratory with two distinct pathways and cumulative threats at both overwintering sites and along the long migratory routes. The migratory group west of the Rocky Mountains moves between coastal California and southern British Columbia. The group east of the Rocky Mountains represents the vast majority of the Canadian population and moves between the Oyamel Forest of central Mexico and southern Canada east of Alberta. The overwintering sites in central Mexico are extremely small, and threats to these areas include illegal logging and agricultural development, and increased frequency and severity of storms during key congregation times. Declines of greater than 50% have occurred over the past decade.
COSEWIC Annual Reports
COSEWIC Annual Report - 2010 (2010-09-03)Under Canada’s Species At Risk Act (SARA), the foremost function of COSEWIC is to “assess the status of each wildlife species considered by COSEWIC to be at risk and, as part of the assessment, identify existing and potential threats to the species”. During the past year, COSEWIC held two Wildlife Species Assessment Meetings and reviewed the status of 79 wildlife species (species, subspecies, populations). During the meeting of November 2009, COSEWIC assessed or reviewed the classification of the status of 28 wildlife species. COSEWIC assessed or reviewed the classification of an additional 51 wildlife species (species, subspecies and populations) during their April 2010 meeting. For species already found on Schedule 1 of SARA, the classification of 32 species was reviewed by COSEWIC and the status of the wildlife species was confirmed to be in the same category (extirpated - no longer found in the wild in Canada but occurring elsewhere, endangered, threatened or of special concern). The wildlife species assessment results for the 2009-2010 reporting period include the following: Extirpated: 6 Endangered: 39 Threatened: 16 Special Concern: 17 Data Deficient: 1 This report transmits to the Minister the status of 46 species newly classified as extirpated, endangered, threatened or of special concern, fulfilling COSEWIC’s obligations under SARA Section 24 and 25. A full detailed summary of the assessment for each species and the reason for the designation can be found in Appendix I of the attached report. Since its inception, COSEWIC has assessed 602 wildlife species in various risk categories, including 262 Endangered, 151 Threatened, 166 Special Concern and 23 Extirpated. In addition, 13 wildlife species have been assessed as Extinct. Also, to date, 46 wildlife species have been identified by COSEWIC as Data Deficient and 166 wildlife species were assessed as Not at Risk. This year has been a particularly productive year for COSEWIC’s Aboriginal Traditional Knowledge (ATK) Subcommittee. In April 2010 COSEWIC approved the Aboriginal Traditional Knowledge Process and Protocol Guidelines, providing clear and agreed principles for the gathering of Aboriginal Traditional Knowledge to carry out COSEWIC functions as required under Section 15(2) of SARA (See Appendix III of the attached report). We are grateful for the rich and enthusiastic contribution made by community elders and experts in helping the ATK Subcommittee prepare the ATK protocols.
COSEWIC Annual Report 2016 to 2017 (2017-10-24)Over the past year COSEWIC re-examined the status of 40 wildlife species; of these, the majority (78 %) were reassessed at the same or lower level of risk. Of a total of 73 species assessed 11 were assigned the status of Not at Risk (8 re-assessments and 3 new assessments). To date and with the submission of this report, COSEWIC’s assessments now include 735 wildlife species in various risk categories including 321 Endangered, 172 Threatened, 219 Special Concern and 23 Extirpated (i.e. - no longer found in the wild in Canada). In addition 16 species have been assessed as Extinct, 58 have been designated as Data Deficient and 186 were assessed and assigned Not at Risk status.