Satyre fauve des Maritimes en péril

Le satyre fauve des Maritimes est l'une des deux seules espèces canadiennes de papillons qui vivent exclusivement dans les marais salés. 

Deux plantes communes doivent y être présentes afin que ce petit papillon puisse y vivre: la spartine étalée et la lavande de mer, que l'on peut trouver dans la plupart des marais salés de l'est du Canada; cependant, le satyre fauve est loin d'y être abondant. 

La totalité de la zone d'existence de cette espèce couvre une aire de moins de deux kilomètres carrés. Les raisons sont inconnues; cependant, étant donné l'expansion urbaine et les polluants aquatiques, les populations de ce papillon sont particulièrement vulnérables.

Hear Reggie
Webster talking
about how this
butterfly got it's
name on:
"Animal Tracks
Episode 7 from
the Discovery Channel"

(photo: Discovery Channel)

The Endangered
Maritime Ringlet Butterfly

Reginald Webster
PHD in Entomology
December 2000

ackground:
The Maritime Ringlet Butterfly, Coenonympha nipisiquit McDunnough, is one of only two species of butterflies in Canada that live exclusively in salt marshes.

The caterpillars of this insect feed on Salt Meadow Cord Grass (Spartina patens) while the adults feed on nectar from the flowers of Sea Lavender (Limonium nashii). These two plants must be present for this small (wing span about 3.5 cm) tan colored butterfly to exist in any given salt marsh. Although these are common plants in most salt marshes in eastern Canada, the Maritime Ringlet, in contrast, is far from widespread. This butterfly is known from only 4 sites near the Chaleur Bay on the east coast of Canada. 

The global range of this species covers an area of less than two square kilometers. It is unclear why this insect has such a restricted global distribution, given the number of suitable salt marshes around Chaleur Bay. The most plausible explanation is that the Maritime Ringlet is a relict species from the previous ice age that now survives in only a few salt marshes, with intervening populations having died out during the retreat of the glaciers.

Reasons for 
endangered species status

The three largest colonies of the Maritime Ringlet occur in salt marshes completely within the city limits of expanding urban areas in Bathurst and Beresford, New Brunswick. These salt marshes are largely privately owned, residential, or recreational properties. Small scale in-filling and clearing of adjacent buffer zone habitats by individual property owners, runoff containing domestic herbicides, pesticides, and lawn fertilizers represent a major threat to this species and are difficult to regulate.

Populations of this butterfly are particularly vulnerable to waterborne pollutants since the entire life cycle of this insect is subjected to periodic flooding by salt water during the tide cycle. All life stages of this insect are at some time exposed to salt water and any pollutants in that water. Although the Maritime Ringlet can at times be locally abundant, with continued urban expansion in this region the cumulative effects of the these factors over time or a major ecological disturbance such as an oil spill, could result in the eventual extinction of this butterfly. It is for these reasons that the Maritime Ringlet has been given endangered species status in New Brunswick and by COSEWIC (Committee on the Status of Endangered Wildlife in Canada).

 

Steps to protect the
Maritime Ringlet

The endangered species legislation of New Brunswick protects the Maritime Ringlet and its habitat. However, unlike other endangered species, which often have restricted ranges, few have the major portion of their distribution completely within developing urban areas. Therefore, additional measures are required for the long-term survival of this "urban" species. Over the past 7 years considerable research has been conducted to obtain information critical for developing a management plan for this species. The life cycle, resource requirements of the immature stages and adults, female reproductive potential, and micro-habitat requirements of the species have been elucidated. Detailed population and vegetation studies have been done. This baseline information is critical for detecting future changes in population numbers and plant communities within the salt marsh. 

A long-term population-monitoring program has been in place since 1997 and research has begun to try to establish new populations of the Maritime Ringlet in unoccupied salt marshes in the region.

(photo: N. Arseneault) =================================== The salt marsh habitat of the Maritime Ringlet near Beresford, N.B. at high tide during the full moon. The highest tides occur when there is either a full moon or new moon. All of the salt marsh vegetation and immature stages of the Maritime Ringlet are covered with salt water for several hours during high tide.   ===================================

 

Much of the above research effort has been supported by The Endangered Species Recovery Fund of the World Wildlife Fund, The New Brunswick Environmental Trust Fund, The New Brunswick Wildlife Council Trust Fund, Noranda, The New Brunswick Department of Natural Resources & Energy and the Canadian Forest Service. Two populations of the Maritime Ringlet at the Daly Point Reserve and Carron Point are protected through corporate stewardship agreements with Noranda and the Province of New Brunswick. These salt marshes and surrounding habitats, which are owned by Noranda, have been established as nature reserves. 

Steps have been initiated to establish stewardship agreements with the numerous landowners of the salt marsh in the estuary of the Peters River in Bathurst and Bereford, which is home to the largest population of the Maritime Ringlet. Gilles Godin, the regional biologist of the N.B. Department of Natural Resources and Energy in Bathurst is playing a lead role in this process. Numerous personnel from the Province, municipalities of Bathurst and Beresford, and non-government organizations have played a critical role in securing funding for research and establishment of current stewardship agreements. 

It is hoped that these continuing efforts will ensure that this unusual butterfly will continue to fly through these salt marshes in the future.

 

(Photo: Reggie Webster)

=================================== The salt marsh habitat of the Maritime Ringlet near Beresford, N.B. at low tide. Note the housing development along the barrier beach adjacent to the salt marsh. The entire barrier beach is now developed.  Development is also occurring along the inland side of the salt marsh ===================================