Elkhorn Slough Foundation

Nonprofit profile at a glance

EIN
942823247
IRS 990 coverage
2010–2024
Forms available
Form 990 2024
Location
Moss Landing, CA, USA
Phone
8317285939
Rating
79
Verdict
SUPPORTED
Rating confidence
Moderate
Sector
Private Independent Foundations

Official website

Reported finances

Revenue
$8,549,320
Expenses
$5,853,417
Assets
$49,727,926
Liabilities
$775,220

Source: IRS Form 990. Selected filing: tax year 2024. Amounts in USD.

Leadership & pay

19 people listed

Executive titles in this filing

  • Mark Silberstein (Executive Director)
  • Susan Matcham (President)
  • Tara Trautsch (Vice President)

Highest reported compensation

  • Mark Silberstein (Executive Director): $198,680 total reported compensation
  • Monique Fountain (Tidal Wetlands Program Director): $149,338 total reported compensation
  • Taylor Honrath (Deputy Director): $132,187 total reported compensation

Source: IRS Form 990. Selected filing: tax year 2024. Names and roles reflect this filing, not necessarily current officeholders.

Overview

Mission

The Elkhorn Slough Foundation's mission is to conserve and restore Elkhorn Slough and its watershed, California's largest tidal salt marsh south of San Francisco Bay. Renowned for its extraordinary biodiversity, Elkhorn Slough features a dynamic working landscape intertwined with rich natural habitats. To achieve its mission, the Elkhorn Slough Foundation focuses on the direct acquisition and stewardship of key lands while collaborating with partnerorganizations and agencies. Together, they advance sound scientific research, deliver impactful education programs, and foster meaningful community engagement. As an accredited organization through the Land Trust Alliance Accreditation Commission, the Foundation upholds the highest standards in conservation and land stewardship.

What it reported doing in 2024

ESF's Education and Public Relations Program (EPR) includes a vibrant social media presence and various public talks, walks, and programs designed for school and community groups. Each year, we support more than 20 outside organizations by providing volunteer opportunities for groups such as Scouting America, church groups, school groups, corporate volunteer programs, and more. Our outdoor education program engages over 150 local students by helping them build meaningful relationships with their peers and the natural environment. For example, students from Hall Elementary School have the opportunity to regularly experience open spaces through ~15 half-day visits per school year. In 2025, we doubled the number of local university students involved in our community programs from 23 to 46. These students, from California State University Monterey Bay, are completing Community Engagement Capstone Projects by helping us deliver programming to elementary school students and families in the community. Among other things, these students are learning how to develop culturally relevant programs that are consciously co-designed with participants, connecting families to the land and water in their communities through projects that remove barriers to access.We also continue to strengthen partnerships with like-minded organizations to conserve and restore Elkhorn Slough and educate the community about its ecological significance. This includes active participation in Juntxs En La Naturaleza, a collaborative group that includes the Monterey Bay Aquarium, Bird School Project, Latino Outdoors, Puentes Nature, Milpa, Regeneracion, and others. Together, we provide access to nature for 300+ historically underserved families in our community. Additionally, we support education and volunteer programs at the Elkhorn Slough Reserve, which served 2,750 students and 21,000 visitors in 2025.

Operating model

Revenue model
Mixed. Its operating money came from several sources; no one source provided a clear majority.
Distribution model
Direct operator. The filing allocates 100% of reported program-service expenses outside its grant, affiliate-payment, and member-benefit lines. This expense classification does not rule out separately announced grant awards.
  • Includes noncash contributions: Reported contributions include donated property or goods.

The verdict

SUPPORTED - The filed numbers largely add up and a large share of total spending goes to programs. A relatively small share of available resources goes toward mission work and fundraising costs are high for each dollar raised.

Rating breakdown

  • Financial Efficiency: 62
  • Transparency & Controls: 84
  • Accountability: 100
  • Sustainability: 79
  • Growth: 100

Detailed rating inputs

Financial Efficiency

  • Mission deployment rate: 55.8%; rating input score 56
  • Program expense ratio: 75.3%; rating input score 75
  • Fundraising efficiency: $15.79 raised per $1 spent on fundraising; rating input score 52; 52nd percentile among comparable filings

Transparency & Controls

  • Consistency checks: 100%; rating input score 100; 63rd percentile among comparable filings
  • Pay-setting controls: 4 of 6 controls in place; rating input score 67
    • Compensation committee: Pass
    • Independent consultant: Missing
    • Other Form 990s reviewed: Pass
    • Written employment contract: Missing
    • Compensation survey or study: Pass
    • Board or committee approval: Pass
  • Foreign activity oversight: Limited
  • Grant itemization coverage: Limited
  • Major donor itemization: Yes; rating input score 100
  • Related-party transparency: Limited

Accountability

  • Independent voting board: 100%; rating input score 100; 63rd percentile among comparable filings
  • Governance controls: 8 of 8 controls in place; rating input score 100
    • Conflict-of-interest policy: Pass
    • Whistleblower policy: Pass
    • Document-retention policy: Pass
    • CEO compensation review process: Pass
    • Other executive compensation review process: NotApplicable
    • Form 990 shared with the board: Pass
    • Board meeting minutes documented: Pass
    • Audit committee oversight: Pass
    • Independent financial-statement audit: Pass

Sustainability

  • Operating margin: 31.5%; rating input score 85; 85th percentile among comparable filings
  • Total-asset coverage ratio: 8.5; rating input score 89; 89th percentile among comparable filings
  • Liabilities to assets ratio: 0.02; rating input score 83; 83rd percentile among comparable filings
  • Officer compensation ratio: 10%; rating input score 30; 30th percentile among comparable filings

Growth

  • Program expense growth: 7.2% per year; rating input score 100; 52nd percentile among comparable filings
  • Revenue growth: 5.6% per year; rating input score 100; 46th percentile among comparable filings
  • Asset growth: 4.5% per year; rating input score 100; 32nd percentile among comparable filings

Details

  • Where the money goes: 55.8% of revenue deployed · 75.3% of spending went to programs
  • Governance: 12 of 12 board members independent · 8 of 8 filing controls reported
  • Programs: 6 filed program accomplishments · $4.4M in reported program spending
  • Leadership: top reported pay $199K · 19 people listed · 4 of 6 pay-setting controls reported
  • Highest-paid contractors: 3 contractors listed · $528K reported
  • Consistency: 36 of 36 current checks pass
  • Schedules: 7 filed schedules · includes major donors and executive pay
  • Filing history: 15 filing years from 2010 to 2024
  • Contacts: How to reach this organization
  • Money network: 4 filed money-flow records
  • Related organizations: Filed and resolved organization relationships.
  • Grant readiness: Federal tax and exclusion status, award history, and grant-maker relationships.
  • People: Everyone the filings name, and which of them the filings identify by more than a name.

Key Signals

Signals prioritize questions for review. They are not findings of misconduct.

Grant-readiness screening is separate from the live rating, not a measure of program quality. Review the source records before making a grant decision.

  • Review — Financial Efficiency: Mission deployment rate scored 56/100.
  • Review — Financial Efficiency: Fundraising efficiency scored 52/100.
  • Moderate — Sustainability: Officer compensation ratio scored 30/100.
  • High — Grant Readiness: Federal audit findings: this organization reported findings in its latest federal Single Audit.