Elkhorn Slough Foundation
Organization summary
Type of Nonprofit
Designated as a Organizations for any of the following purposes: religious, educational, charitable, scientific, literary, testing for public safety, fostering national or international amateur sports competition (as long as it doesn't provide athletic facilities or equipment), or the prevention of cruelty to children or animals.
Category: Philanthropy, Voluntarism and Grantmaking Foundations / Private Independent Foundations (NTEE)
Donations to this organization are tax deductible.
Summary charts: organization finances over time
Revenue $9.67M (2024)
Expenses $5.43M (2024)
Total Assets $46.8M (2024)
Total Liabilities $603k (2024)
Tax Filings and Audits by Year
Form 990 is an information return that most organizations claiming federal tax-exempt status must file yearly with the IRS. Nonprofit Explorer has IRS digitized Form 990 data for filings processed in 2012 and later. If this organization filed an amended return, it may not be reflected below. Duplicate download links may indicate a resubmission or amendment to this organization's original return. Form 990 data is from the IRS.
Audits are required to be submitted by nonprofit organizations that spend $750,000 or more in federal grant money in a fiscal year. "Single audits" look at the entire organization's finances and compliance, while other audits are program specific. Nonprofit Explorer has PDFs of audits for some nonprofits for fiscal year 2015 and later. Audit data is from the Federal Audit Clearinghouse.
Fiscal Year Ending June
2024
Extracted Financial Data
Extracted Financial Data from Form 990
| Notable Sources of Revenue | Percent of Total Revenue | |
|---|---|---|
| Contributions | $8,994,082 |
93.0%
|
| Program Services | $34,533 |
0.4%
|
| Investment Income | $349,702 |
3.6%
|
| Bond Proceeds | $0 | |
| Royalties | $0 | |
| Rental Property Income | $160,056 |
1.7%
|
| Net Fundraising | $0 | |
| Sales of Assets | $126,879 |
1.3%
|
| Net Inventory Sales | $5,376 |
0.1%
|
| Other Revenue | $3,553 |
0.0%
|
| Notable Expenses | Percent of Total Expenses | |
|---|---|---|
| Executive Compensation | $314,117 |
5.8%
|
| Professional Fundraising Fees | $0 | |
| Other Salaries and Wages | $1,710,406 |
31.5%
|
| Assets/Debt | ||
|---|---|---|
| Total Assets | $46,787,248 | |
| Total Liabilities | $603,474 |
Compensation
| Key Employees and Officers | Compensation | Related | Other |
|---|---|---|---|
| Mark Silberstein (Executive Director) | $173,768 | $0 | $10,954 |
| Taylor Honrath (Associate Director) | $105,542 | $0 | $15,359 |
| Monique Fountain (Tidal Wetlands Program Director) | $100,460 | $0 | $24,954 |
Document Links
990
Filed on April 9, 2025Primary tax return for a nonprofit’s activities, finances, and governance
Audit
Audit for an entity that spends $750,000+ in federal grant money in a fiscal year
Fiscal Year Ending June
2023
Extracted Financial Data
Extracted Financial Data from Form 990
| Notable Sources of Revenue | Percent of Total Revenue | |
|---|---|---|
| Contributions | $4,605,603 |
87.8%
|
| Program Services | $60,152 |
1.1%
|
| Investment Income | $272,123 |
5.2%
|
| Bond Proceeds | $0 | |
| Royalties | $0 | |
| Rental Property Income | $151,816 |
2.9%
|
| Net Fundraising | $0 | |
| Sales of Assets | $19,420 |
0.4%
|
| Net Inventory Sales | $3,656 |
0.1%
|
| Other Revenue | $133,103 |
2.5%
|
| Notable Expenses | Percent of Total Expenses | |
|---|---|---|
| Executive Compensation | $193,882 |
4.2%
|
| Professional Fundraising Fees | $0 | |
| Other Salaries and Wages | $1,601,875 |
34.6%
|
| Assets/Debt | ||
|---|---|---|
| Total Assets | $42,556,988 | |
| Total Liabilities | $1,051,831 |
Compensation
| Key Employees and Officers | Compensation | Related | Other |
|---|---|---|---|
| Mark Silberstein (Executive Direc) | $173,640 | $0 | $17,883 |
| Monique Fountain (Tidal Wetlands Project Director) | $102,920 | $0 | $0 |
| Anne Secker (Treasurer) | $0 | $0 | $0 |
Document Links
990
Filed on May 15, 2024Primary tax return for a nonprofit’s activities, finances, and governance
Audit
Audit for an entity that spends $750,000+ in federal grant money in a fiscal year
This audit found:
Fiscal Year Ending June
2022
Extracted Financial Data
Extracted Financial Data from Form 990
| Notable Sources of Revenue | Percent of Total Revenue | |
|---|---|---|
| Contributions | $3,424,824 |
74.3%
|
| Program Services | $79,588 |
1.7%
|
| Investment Income | $198,916 |
4.3%
|
| Bond Proceeds | $0 | |
| Royalties | $0 | |
| Rental Property Income | $138,300 |
3.0%
|
| Net Fundraising | $2,197 |
0.0%
|
| Sales of Assets | $428,625 |
9.3%
|
| Net Inventory Sales | $2,785 |
0.1%
|
| Other Revenue | $331,921 |
7.2%
|
| Notable Expenses | Percent of Total Expenses | |
|---|---|---|
| Executive Compensation | $186,559 |
4.5%
|
| Professional Fundraising Fees | $0 | |
| Other Salaries and Wages | $1,439,092 |
34.8%
|
| Assets/Debt | ||
|---|---|---|
| Total Assets | $41,261,031 | |
| Total Liabilities | $768,148 |
Compensation
| Key Employees and Officers | Compensation | Related | Other |
|---|---|---|---|
| Mark Silberstein (Executive Direc) | $173,640 | $0 | $11,560 |
| Gary Bloom (Trustee) | $0 | $0 | $0 |
| Tara Trautsch (Secretary) | $0 | $0 | $0 |
Document Links
990
Filed on Aug. 7, 2023Primary tax return for a nonprofit’s activities, finances, and governance
Audit
Audit for an entity that spends $750,000+ in federal grant money in a fiscal year
This audit found:
Fiscal Year Ending June
2021
Extracted Financial Data
Extracted Financial Data from Form 990
| Notable Sources of Revenue | Percent of Total Revenue | |
|---|---|---|
| Contributions | $5,546,633 |
88.7%
|
| Program Services | $30,266 |
0.5%
|
| Investment Income | $188,008 |
3.0%
|
| Bond Proceeds | $0 | |
| Royalties | $0 | |
| Rental Property Income | $158,821 |
2.5%
|
| Net Fundraising | $0 | |
| Sales of Assets | $181,026 |
2.9%
|
| Net Inventory Sales | -$3,102 | |
| Other Revenue | $151,002 |
2.4%
|
| Notable Expenses | Percent of Total Expenses | |
|---|---|---|
| Executive Compensation | $177,062 |
3.7%
|
| Professional Fundraising Fees | $0 | |
| Other Salaries and Wages | $1,393,769 |
29.0%
|
| Assets/Debt | ||
|---|---|---|
| Total Assets | $43,540,960 | |
| Total Liabilities | $1,870,822 |
Compensation
| Key Employees and Officers | Compensation | Related | Other |
|---|---|---|---|
| Mark Silberstein (Executive Direc) | $177,225 | $0 | $0 |
| Gary Bloom (Trustee) | $0 | $0 | $0 |
| Tara Trautsch (Secretary) | $0 | $0 | $0 |
Document Links
990
Filed on May 12, 2022Primary tax return for a nonprofit’s activities, finances, and governance
Audit
Audit for an entity that spends $750,000+ in federal grant money in a fiscal year
Fiscal Year Ending June
2020
Extracted Financial Data
Extracted Financial Data from Form 990
| Notable Sources of Revenue | Percent of Total Revenue | |
|---|---|---|
| Contributions | $3,501,956 |
84.7%
|
| Program Services | $75,566 |
1.8%
|
| Investment Income | $204,068 |
4.9%
|
| Bond Proceeds | $0 | |
| Royalties | $0 | |
| Rental Property Income | $168,094 |
4.1%
|
| Net Fundraising | $0 | |
| Sales of Assets | $39,228 |
0.9%
|
| Net Inventory Sales | $15,838 |
0.4%
|
| Other Revenue | $130,874 |
3.2%
|
| Notable Expenses | Percent of Total Expenses | |
|---|---|---|
| Executive Compensation | $178,411 |
4.6%
|
| Professional Fundraising Fees | $0 | |
| Other Salaries and Wages | $1,403,395 |
35.8%
|
| Assets/Debt | ||
|---|---|---|
| Total Assets | $40,813,318 | |
| Total Liabilities | $2,050,226 |
Compensation
| Key Employees and Officers | Compensation | Related | Other |
|---|---|---|---|
| Mark Silberstein (Executive Direc) | $173,536 | $0 | $3,236 |
| Gary Bloom (Trustee) | $0 | $0 | $0 |
| Tara Trautsch (Trustee) | $0 | $0 | $0 |
Document Links
990
Filed on May 14, 2021Primary tax return for a nonprofit’s activities, finances, and governance
Audit
Audit for an entity that spends $750,000+ in federal grant money in a fiscal year
Fiscal Year Ending June
2019
Extracted Financial Data
Extracted Financial Data from Form 990
| Notable Sources of Revenue | Percent of Total Revenue | |
|---|---|---|
| Contributions | $3,144,527 |
82.0%
|
| Program Services | $59,714 |
1.6%
|
| Investment Income | $219,139 |
5.7%
|
| Bond Proceeds | $0 | |
| Royalties | $0 | |
| Rental Property Income | $198,524 |
5.2%
|
| Net Fundraising | $0 | |
| Sales of Assets | $86,065 |
2.2%
|
| Net Inventory Sales | $16,101 |
0.4%
|
| Other Revenue | $111,170 |
2.9%
|
| Notable Expenses | Percent of Total Expenses | |
|---|---|---|
| Executive Compensation | $163,143 |
4.7%
|
| Professional Fundraising Fees | $0 | |
| Other Salaries and Wages | $1,320,632 |
37.7%
|
| Assets/Debt | ||
|---|---|---|
| Total Assets | $39,920,439 | |
| Total Liabilities | $1,162,010 |
Compensation
| Key Employees and Officers | Compensation | Related | Other |
|---|---|---|---|
| Mark Silberstein (Executive Direc) | $138,607 | $0 | $4,118 |
| Lorili Toth (Dev. Director) | $101,880 | $0 | $15,267 |
| Gary Bloom (Trustee) | $0 | $0 | $0 |
Document Links
990
Filed on June 11, 2020Primary tax return for a nonprofit’s activities, finances, and governance
Audit
Audit for an entity that spends $750,000+ in federal grant money in a fiscal year
Fiscal Year Ending June
2018
Extracted Financial Data
Extracted Financial Data from Form 990
| Notable Sources of Revenue | Percent of Total Revenue | |
|---|---|---|
| Contributions | $4,113,832 |
38.3%
|
| Program Services | $56,215 |
0.5%
|
| Investment Income | $166,190 |
1.5%
|
| Bond Proceeds | $0 | |
| Royalties | $0 | |
| Rental Property Income | $181,456 |
1.7%
|
| Net Fundraising | $0 | |
| Sales of Assets | $347,302 |
3.2%
|
| Net Inventory Sales | $15,647 |
0.1%
|
| Other Revenue | $5,868,775 |
54.6%
|
| Notable Expenses | Percent of Total Expenses | |
|---|---|---|
| Executive Compensation | $144,030 |
3.2%
|
| Professional Fundraising Fees | $0 | |
| Other Salaries and Wages | $1,131,999 |
25.1%
|
| Assets/Debt | ||
|---|---|---|
| Total Assets | $40,888,858 | |
| Total Liabilities | $2,591,159 |
Compensation
| Key Employees and Officers | Compensation | Related | Other |
|---|---|---|---|
| Mark Silberstein (Executive Direc) | $138,554 | $0 | $4,079 |
| Lorili Toth (Dev. Director) | $104,389 | $0 | $13,972 |
| Tara Trautsch (Trustee) | $0 | $0 | $0 |
Document Links
990
Filed on March 18, 2019Primary tax return for a nonprofit’s activities, finances, and governance
Audit
Audit for an entity that spends $750,000+ in federal grant money in a fiscal year
Fiscal Year Ending June
2017
Extracted Financial Data
Extracted Financial Data from Form 990
| Notable Sources of Revenue | Percent of Total Revenue | |
|---|---|---|
| Contributions | $1,898,069 |
72.0%
|
| Program Services | $69,778 |
2.6%
|
| Investment Income | $130,799 |
5.0%
|
| Bond Proceeds | $0 | |
| Royalties | $0 | |
| Rental Property Income | $178,706 |
6.8%
|
| Net Fundraising | $0 | |
| Sales of Assets | $69,671 |
2.6%
|
| Net Inventory Sales | $12,173 |
0.5%
|
| Other Revenue | $277,424 |
10.5%
|
| Notable Expenses | Percent of Total Expenses | |
|---|---|---|
| Executive Compensation | $144,029 |
4.8%
|
| Professional Fundraising Fees | $0 | |
| Other Salaries and Wages | $1,220,253 |
40.8%
|
| Assets/Debt | ||
|---|---|---|
| Total Assets | $32,765,185 | |
| Total Liabilities | $558,144 |
Compensation
| Key Employees and Officers | Compensation | Related | Other |
|---|---|---|---|
| Mark Silberstein (Executive Direc) | $136,615 | $0 | $7,434 |
| Lorili Toth (Dev. Director) | $105,860 | $0 | $14,128 |
| Judith Connor (Vice President) | $0 | $0 | $0 |
Document Links
990
Filed on Feb. 28, 2018Primary tax return for a nonprofit’s activities, finances, and governance
Audit
Audit for an entity that spends $750,000+ in federal grant money in a fiscal year
Fiscal Year Ending June
2016
Extracted Financial Data
Extracted Financial Data from Form 990
| Notable Sources of Revenue | Percent of Total Revenue | |
|---|---|---|
| Contributions | $3,929,238 |
90.4%
|
| Program Services | $84,630 |
1.9%
|
| Investment Income | $149,404 |
3.4%
|
| Bond Proceeds | $0 | |
| Royalties | $0 | |
| Rental Property Income | $175,968 |
4.0%
|
| Net Fundraising | $0 | |
| Sales of Assets | -$16,670 | |
| Net Inventory Sales | $15,865 |
0.4%
|
| Other Revenue | $10,467 |
0.2%
|
| Notable Expenses | Percent of Total Expenses | |
|---|---|---|
| Executive Compensation | $154,256 |
6.4%
|
| Professional Fundraising Fees | $0 | |
| Other Salaries and Wages | $1,208,126 |
50.1%
|
| Assets/Debt | ||
|---|---|---|
| Total Assets | $32,741,932 | |
| Total Liabilities | $625,925 |
Compensation
| Key Employees and Officers | Compensation | Related | Other |
|---|---|---|---|
| Mark Silberstein (Executive Direc) | $134,791 | $0 | $17,168 |
| Lorili Toth (Dev. Director) | $105,410 | $0 | $17,113 |
| Judith Connor (Vice President) | $0 | $0 | $0 |
Document Links
990
Filed on Feb. 15, 2017Primary tax return for a nonprofit’s activities, finances, and governance
Fiscal Year Ending June
2015
Extracted Financial Data
Extracted Financial Data from Form 990
| Notable Sources of Revenue | Percent of Total Revenue | |
|---|---|---|
| Contributions | $1,827,703 |
85.0%
|
| Program Services | $77,396 |
3.6%
|
| Investment Income | $115,557 |
5.4%
|
| Bond Proceeds | $0 | |
| Royalties | $0 | |
| Rental Property Income | $177,507 |
8.3%
|
| Net Fundraising | $0 | |
| Sales of Assets | -$71,247 | |
| Net Inventory Sales | $18,026 |
0.8%
|
| Other Revenue | $5,061 |
0.2%
|
| Notable Expenses | Percent of Total Expenses | |
|---|---|---|
| Executive Compensation | $155,561 |
6.5%
|
| Professional Fundraising Fees | $0 | |
| Other Salaries and Wages | $1,115,254 |
46.3%
|
| Assets/Debt | ||
|---|---|---|
| Total Assets | $30,818,947 | |
| Total Liabilities | $574,815 |
Compensation
| Key Employees and Officers | Compensation | Related | Other |
|---|---|---|---|
| Mark Silberstein (Executive Direc) | $130,753 | $0 | $18,813 |
| Lorili Toth (Dev. Director) | $106,455 | $0 | $16,769 |
| Steve Green (Trustee) | $0 | $0 | $0 |
Document Links
990
Filed on Jan. 26, 2016Primary tax return for a nonprofit’s activities, finances, and governance
Fiscal Year Ending June
2014
Extracted Financial Data
Extracted Financial Data from Form 990
| Notable Sources of Revenue | Percent of Total Revenue | |
|---|---|---|
| Contributions | $2,905,605 |
81.2%
|
| Program Services | $102,798 |
2.9%
|
| Investment Income | $273,118 |
7.6%
|
| Bond Proceeds | $0 | |
| Royalties | $0 | |
| Rental Property Income | $161,448 |
4.5%
|
| Net Fundraising | $0 | |
| Sales of Assets | $107,222 |
3.0%
|
| Net Inventory Sales | $21,185 |
0.6%
|
| Other Revenue | $7,998 |
0.2%
|
| Notable Expenses | Percent of Total Expenses | |
|---|---|---|
| Executive Compensation | $154,584 |
5.7%
|
| Professional Fundraising Fees | $0 | |
| Other Salaries and Wages | $1,102,605 |
40.8%
|
| Assets/Debt | ||
|---|---|---|
| Total Assets | $31,628,907 | |
| Total Liabilities | $1,083,042 |
Compensation
| Key Employees and Officers | Compensation | Related | Other |
|---|---|---|---|
| Mark Silberstein (Executive Direc) | $122,479 | $0 | $27,083 |
| Steve Green (Trustee) | $0 | $0 | $0 |
| Judith Connor (President) | $0 | $0 | $0 |
Document Links
990
Filed on Feb. 25, 2015Primary tax return for a nonprofit’s activities, finances, and governance
Fiscal Year Ending June
2013
Extracted Financial Data
Extracted Financial Data from Form 990
| Notable Sources of Revenue | Percent of Total Revenue | |
|---|---|---|
| Contributions | $6,154,788 |
93.2%
|
| Program Services | $102,097 |
1.5%
|
| Investment Income | $134,757 |
2.0%
|
| Bond Proceeds | $0 | |
| Royalties | $0 | |
| Rental Property Income | $148,289 |
2.2%
|
| Net Fundraising | $2,496 |
0.0%
|
| Sales of Assets | $28,366 |
0.4%
|
| Net Inventory Sales | $15,121 |
0.2%
|
| Other Revenue | $19,700 |
0.3%
|
| Notable Expenses | Percent of Total Expenses | |
|---|---|---|
| Executive Compensation | $163,189 |
6.4%
|
| Professional Fundraising Fees | $0 | |
| Other Salaries and Wages | $1,063,175 |
41.6%
|
| Assets/Debt | ||
|---|---|---|
| Total Assets | $29,835,998 | |
| Total Liabilities | $824,924 |
Document Links
990
Filed on March 18, 2014Primary tax return for a nonprofit’s activities, finances, and governance
Fiscal Year Ending June
2012
Extracted Financial Data
Extracted Financial Data from Form 990
| Notable Sources of Revenue | Percent of Total Revenue | |
|---|---|---|
| Contributions | $1,718,666 |
83.5%
|
| Program Services | $188,169 |
9.1%
|
| Investment Income | $90,760 |
4.4%
|
| Bond Proceeds | $0 | |
| Royalties | $0 | |
| Rental Property Income | $69,091 |
3.4%
|
| Net Fundraising | $0 | |
| Sales of Assets | -$21,473 | |
| Net Inventory Sales | $12,495 |
0.6%
|
| Other Revenue | $66 |
0.0%
|
| Notable Expenses | Percent of Total Expenses | |
|---|---|---|
| Executive Compensation | $146,673 |
5.9%
|
| Professional Fundraising Fees | $0 | |
| Other Salaries and Wages | $1,160,653 |
46.6%
|
| Assets/Debt | ||
|---|---|---|
| Total Assets | $24,877,782 | |
| Total Liabilities | $407,492 |
Document Links
990
Primary tax return for a nonprofit’s activities, finances, and governance
Fiscal Year Ending June
2011
Extracted Financial Data
Extracted Financial Data from Form 990
| Notable Sources of Revenue | Percent of Total Revenue | |
|---|---|---|
| Contributions | $4,205,126 |
90.1%
|
| Program Services | $142,499 |
3.1%
|
| Investment Income | $83,558 |
1.8%
|
| Bond Proceeds | $0 | |
| Royalties | $0 | |
| Rental Property Income | $48,017 |
1.0%
|
| Net Fundraising | $0 | |
| Sales of Assets | $152,269 |
3.3%
|
| Net Inventory Sales | $32,046 |
0.7%
|
| Other Revenue | $3,707 |
0.1%
|
| Notable Expenses | Percent of Total Expenses | |
|---|---|---|
| Executive Compensation | $142,108 |
3.0%
|
| Professional Fundraising Fees | $0 | |
| Other Salaries and Wages | $1,375,605 |
29.4%
|
| Assets/Debt | ||
|---|---|---|
| Total Assets | $25,438,036 | |
| Total Liabilities | $401,459 |
Document Links
990
Primary tax return for a nonprofit’s activities, finances, and governance
Fiscal Year Ending June
2010
No Extracted Financial Data
Extracted financial data is not available for the forms filed in this tax period, but Form 990 documents are available for download.
Document Links
990
Primary tax return for a nonprofit’s activities, finances, and governance
Fiscal Year Ending June
2009
No Extracted Financial Data
Extracted financial data is not available for the forms filed in this tax period, but Form 990 documents are available for download.
Document Links
990
Primary tax return for a nonprofit’s activities, finances, and governance
Fiscal Year Ending June
2008
No Extracted Financial Data
Extracted financial data is not available for the forms filed in this tax period, but Form 990 documents are available for download.
Document Links
990
Primary tax return for a nonprofit’s activities, finances, and governance
Fiscal Year Ending June
2007
No Extracted Financial Data
Extracted financial data is not available for the forms filed in this tax period, but Form 990 documents are available for download.
Document Links
990
Primary tax return for a nonprofit’s activities, finances, and governance
Fiscal Year Ending June
2006
No Extracted Financial Data
Extracted financial data is not available for the forms filed in this tax period, but Form 990 documents are available for download.
Document Links
990
Primary tax return for a nonprofit’s activities, finances, and governance
Fiscal Year Ending June
2005
No Extracted Financial Data
Extracted financial data is not available for the forms filed in this tax period, but Form 990 documents are available for download.
Document Links
990
Primary tax return for a nonprofit’s activities, finances, and governance
Fiscal Year Ending Dec.
2004
No Extracted Financial Data
Extracted financial data is not available for the forms filed in this tax period, but Form 990 documents are available for download.
Document Links
990
Primary tax return for a nonprofit’s activities, finances, and governance
Fiscal Year Ending Dec.
2003
No Extracted Financial Data
Extracted financial data is not available for the forms filed in this tax period, but Form 990 documents are available for download.
Document Links
990
Primary tax return for a nonprofit’s activities, finances, and governance
Fiscal Year Ending Dec.
2002
No Extracted Financial Data
Extracted financial data is not available for the forms filed in this tax period, but Form 990 documents are available for download.
Document Links
990
Primary tax return for a nonprofit’s activities, finances, and governance
Fiscal Year Ending Dec.
2001
No Extracted Financial Data
Extracted financial data is not available for the forms filed in this tax period, but Form 990 documents are available for download.
Document Links
990
Primary tax return for a nonprofit’s activities, finances, and governance
About This Data
Nonprofit Explorer includes summary data for nonprofit tax returns and full Form 990 documents, in both PDF and digital formats.
The summary data contains information processed by the IRS during the 2012-2019 calendar years; this generally consists of filings for the 2011-2018 fiscal years, but may include older records. This data release includes only a subset of what can be found in the full Form 990s.
In addition to the raw summary data, we link to PDFs and digital copies of full Form 990 documents wherever possible. This consists of separate releases by the IRS of Form 990 documents processed by the agency, which we update regularly.
We also link to copies of audits nonprofit organizations that spent $750,000 or more in Federal grant money in a single fiscal year since 2016. These audits are copied from the Federal Audit Clearinghouse.