San Diego Zoo Global Plant Conservation and Native Seed Banking

Joyce Maschinski

Center for Plant Conservation and San Diego Zoo Global

The State of Plant EndangermentThe Planet • Over 350,000 plant species• New species are being described daily. • 20% threatened with extinction

United States and Canada • 4400 plant species at risk of extinction

San Diego County• 19 US Endangered &Threatened• 79 Globally rare (G1 & G2) • 133 California Rarest (CNPS 1B.1, 8%)

Low recruitment Habitat loss Invasive plants

What factors threaten plant populations?

Inappropriate Fire Frequency

San Diego Zoo Global FIGHTs against extinction of animal AND PLANT species

• Ex-situ Conservation• Seed Bank

• Conservation Collections

• Living Gene Banks

• Frozen Garden (Cryopreservation)

• Germplasm

• Recalcitrant species

• Research• Plant Genetics

• Population Studies

• Conserving Genetic Diversity

• Germination Studies

• Propagation Studies

• Restoration• Seed Bulking

• Reintroductions

Where?

How many?

How arethey doing? What is the problem?

Solutions:Research

Ex situ collection

Reintroduction &Restoration

Remove threats

Follow up

Full Spectrum Conservation for Species’ Recovery

What?

Processing, Testing and Storing Seed Long-Term

Otay Mesa Mint (Pogogynenudiuscula) US Endangered

California Orcutt grass (Orcuttia californica) US Endangered

spreading navarretia(Navarretia fossalis) US T

willowy monardella(Monardella viminea), US Endangered

Orcutt’s bird’s-beak (Dicranostegia orcuttiana), CA 2.B; common elsewhere

San Diego thornmint(Acanthomintha ilicifolia)US Threatened

salt marsh bird’s-beak (Chloropyron maritimum spp. maritimum), US Endangered

Mexican flannelbush(Fremontodendron mexicanum)US Endangered

little mousetail(Myosurus minimus ssp. apus) County Sp of concern

Short-leafed dudleya(Dudleya brevifolia)CA Endangered

SANDAG Funded Target Rare Plant Collections

Conservation Collections• Follow Center for Plant

Conservation Guidelines to maximize the genetic diversity in the collection

• 50 mother plants/ population

• from at least 5 populations

• Capture diversity across space, time, appearance & ecology.

• Have conservation mandate –support species’ survival in wild

San Diego Thornmint Seeds, Photo by John MacDonald, Rancho Santa Ana Botanic Garden

San Diego thornmint(Acanthomintha ilicifolia)US Threatened; CA Endangered; Global Rank = G1• Annual In 2009 55 occurrences

San Diego County• 13 in Mexico (though status of

populations is unknown)

Rare Plant Collection Targets

San Diego Thornmint Genetic Analysis by Elizabeth R. Milano USGS

Genetic ClustersK=5

Mem

ber

ship

Pro

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ility

0

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1253 15

The Link Between the SDZG Native Seed Bank and Restoration

• Safeguard populations

• Provide propagules for research and restoration

• Improve ecosystem health through restoration

Seed Bulking With SANDAG Funding Reintroductions to Vernal Pools in 2018 & 2019 with CollaboratorsMission Trails Regional Park & Chaparral Lands Conservancy

Species Location of collection

Approximate Number of

Seeds

Number of Maternal

Lines

San Diego thornmint

DenneryRanch

14300 20

San Diego thornmint

Mission Trails 2025 34

California Orcutt’sGrass

DenneryCanyon

49670 27

Little MousetailDennery Canyon

1,215,838 80

Orcutt’s bird’s beakDennery

Ranch0 0

Understanding Propagation Requirements of Rare Species is Essential Prior to Restoration

Restorations Dec 2018 & Jan 2019

Ending Plant Extinction in San Diego County

• Prioritizing and collecting strategically across breadth of the species range

• Collecting across time to capture years of good population growth that follows good rainfall.

• Maintaining healthy seed collections

• Using seeds to seed or bulk and grow to restore wild populations

It Takes a Village!

Thanks to SANDAG for funding support, CPC and SDZG Plant Conservation Team and partners at City of San Diego, Mission Trails Regional Park, & Chaparral Lands Conservancy.