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Monarch cluster
General News

ESA Listing Decision Announced

After careful consideration, the USFWS has determined that monarchs are "threatened" - they are likely to become endangered in the foreseeable future through a significant portion of their range

Alternare receiving award
MBF Updates

Alternare Receives Award from “Fundación Merced”

“Fundación Merced” awarded the “Razón de Ser” (Reason for Being) prize to Alternare acknowledging their institutionality, transparency, responsibility and professionalism.

Drone flying over monarch forest
MBF Updates

Drone Experiments to Assess Climate Change and its Impact on Forest Conditions

Dr. Cuauhtémoc Saénz and PhD Student José Luis Gallardo use drones to assess stress levels of oyamel trees in the monarch areas.

Alternare with other winners receiving award from UNDP
MBF Updates

Alternare Receives Award from the United Nations Development Program (UNDP)

Alternare receives award from UNDP in the "Gender Equality for Environmental Action" category for their work empowering rural women.

Lincoln's network of collaborators
MBF Updates

Remembering Lincoln Brower and His Legacy

On the anniversary of his passing, we celebrate Lincoln Brower - monarch scientist, conservationist and friend.

Photo of Lincoln P Brower

The 2024 LPB Award Recipients Announced

Three excellent student proposals have been accepted for funding.

Monarchs clustering on tree trunks and branches at Rosario
Overwintering Populations

Eastern Monarch Population Decreases by 59.3% in 2023-2024 Overwintering Season

Monarch Winter 2023-2024 Population Numbers Released

MBF Updates

Risk Assessment of Pesticides in the Eastern Avocado Belt

Research on the use of pesticides in the Eastern avocado belt in Michoacán using a survey and water monitoring approach.

Alfredo Ramírez Bedolla, Governor of Michoacán talking in ceremony where funds were given
General News

Mexico's Monarch Fund Receives Contribution from the Government of Michoacán

Governor of Michoacán contributes one million dollars to Mexico's Monarch Fund.

Female monarch on Liatris
General News

Monarchs Ranked as "Endangered" in Canada

Monarchs are now ranked as "Endangered" under Canada’s Species at Risk Act (SARA).

Monarch Butterfly Flight Challenge logo
MBF Updates

Flight Challenge Update - testing mSail functions during 2023-2024 overwintering season

Flight challenge scientists are advancing trying out mSAIL (milligram-scale multi-modal sensor) at the Monarch Butterfly Biosphere Reserve.

Monarch cluster
Overwintering Populations

Rains greet monarchs this 2023-2024 overwintering season

Year to year variation and conditions associated with the El Niño-Southern Oscillation raise questions and concerns about the monarchs' future and how best to conserve this migratory marvel.

Monarchs flying near overwintering forests
Overwintering Populations

Monarchs are settling in at their overwintering sites in 2023-2024 season

Monarch overwintering colonies are dynamic. At this time of year, monarchs are moving about in the forests and establishing their roosts. Read more about this process and see videos of this spectacular phenomenon.

General News

MBF Grantees Explain Their Research in Upcoming MJV Webinar

MBF's grantees, Dr. Cuauhtémoc Sáenz-Romero, and Dr. José Arnulfo Blanco García, are giving a presentation on the impact of climate change on oyamels in the Monarch Butterfly Biosphere Reserve on the Monarch Joint Venture's webinar series on November 14, 2:00 EST.

Map of monarch fall roosts sighted during Fall 2023 migration
Overwintering Populations

Eastern population nearing its overwintering home in 2023-2024 season

Observers collectively track monarch migration via Journey North. Visit the Journey North site for maps and news of the migration.

Project Updates

Monarchs Across Georgia's Fall 2023 Edition of "The Chrysalid" Just Out

Symbolic migration celebrates 28 years!

Monarchs flying and on trees at El Rosario Feb. 2023
Overwintering Populations

Eastern Population Decreases by 22% in 2022-2023 Overwintering Season

Monarch population decreases in 2022-2023 Overwintering Season.

Three images of trees with men evaluating their growth
MBF Updates

Evaluations of Tree Survival Rates in Reforestations

The success of reforestation programs relies on periodic monitoring of trees planted at different periods of time.

View of a tree nursery covered with net
MBF Updates

Reforestation: Step by Step

Reforestation in the monarch’s Mexican overwintering sites is crucial for the monarchs and just as important for the well-being of the local residents.

Carlitos with his parents tending the seedlings in the tree nursery
MBF Updates

The Story of Carlitos and The Trees he Planted

Ten-year-old Carlitos Cruz tells the story of how he planted trees with his parents in 2015, and how the trees are doing today, six years later.

Photo of images taken with drone
Project Updates

Drones Monitoring Monarch Butterfly Biosphere Reserve

Drones are being used as part of the assisted migration research to get information on the health of oyamel trees.

Photo of Lincoln P Brower
MBF Updates

2023 Lincoln P. Brower Award Winners

Graduate student Grace Thomas and undergraduate student Fernanda Naomi Shimizu Romero received the “Lincoln P. Brower Award” in May 2023.

Alternare logo
MBF Updates

Alternare Celebrate their 25th Anniversary

MBF's long-standing partner celebrated their 25th birthday!

Monarch butterfly on white flowers
General News

Migratory Monarchs Listed as Endangered on the IUCN Red List

Monarchs are now listed as an Endangered species on the International Union for Conservation of Nature's Red List of Threatened Species.

Overwintering monarchs covering trees
Overwintering Populations

Monarch Population Increases by 35% in the 2021-2022 Season

Monarch population increases in 2021-2022 overwintering season.

Estela Romero with children holding paper butterflies
MBF Updates

Symbolic Migration Video

Journey North's symbolic migration is shown in this video.

Monarchs clustering on branch
Overwintering Populations

Overwintering Monarchs Occupy 2.10 Hectares in 2020-2021

Monarch population in 2020-2021 overwintering season.

Lincoln Brower with his camera taking a photo of monarchs fluttering about
MBF Updates

Frontiers in Ecology and Evolution Publishes Article About Lincoln Brower

MBF Board members and others wrote an article titled “Lincoln Brower, Champion for Monarchs.”

Woman by her fuel-efficient stove
MBF Updates

Newsweek Mexico Publishes Article on the Monarchs Highlighting Alternare’s Work

A great article on how poverty affects the monarch area and how Alternare, with the support of MBF and many others are helping.

Monarch covering tree trunks
Overwintering Populations

Overwintering Population Increases by 144% in 2018-2019 season

Monarch population increases in 2018-2019 season.

MBF Updates

Remembering Dr. Lincoln P. Brower

Our friend and longtime colleague Lincoln P. Brower passed away on July 17, 2018.