(well, not for rent - the Zoo pays ZERO rent, yes ZERO - Fairmount Park leases the land to the Zoo at no charge)
$297,000.00 - Zoo Director Pete Hoskin's annual compensation according to Charity Navigator (no information available yet for the salary of new zoo director Vik Dewan).
http://www.charitynavigator.org/index.cfm/bay/search.summary/orgid/4801.htm
By comparison:
The Elephant Sanctuary's (Hohenwald, TN) CEO annual compensation is $21,000.
The Performing Animal Welfare Society's ( Galt, CA) CEO annual compensation is $35,861.
The Memphis (TN) Zoo's CEO annual compensation is $118,400.
The Oakland (CA) Zoo's CEO annual compensation is $144,400.
The San Francisco (CA) Zoo's CEO annual compensation is $150,000.
The Denver (CO) Zoo's CEO annual compensation is $154,172.
The Phoenix (AZ) Zoo's CEO annual compensation is $163,231.
The Atlanta (GA) Zoo's CEO annual compensation is $175,000.
The Pittsburgh (PA) Zoo's CEO annual compensation is $181,196.
The Columbus (OH) Zoo's CEO annual compensation is $192,186.
The Woodland Park (Seattle, WA) Zoo'sannual compensation is $202,058.
The Lowry Park (Tampa, FL) Zoo's annual compensation is $204,158.
The Houston (TX) Zoo's CEO annual compensation is $206,051.
Well, not for enrichment - not much anyway. This is the Philly Zoo's idea of enrichment for a tiger ...... a cardboard box.

AUDIT OF THE PHILADELPHIA ZOO - read about recommendations made by city officials over ten years ago, few of which have been implemented.
2004 Expenses of the Philadelphia Zoo
Exhibit and Garden Care $ 11,973,000 - 34%
Animal Care $ 5,512,000 - 16%
General Management and Administration 4,491,000 - 13%
Guest and Member Services 4,790,000 - 13%
Contributed Goods and Services 2,082,000 - 6%
Marketing and Advertising 1,535,000 - 4%
Development and Fundraising 2,590,000 - 7%
Education and Conservation 2,436,000 - 7%
2003 Expenses of the Philadelphia Zoo
Exhibit and Garden Care 6,491,000 - 19%
Animal Care $ 5,064,000 - 15%
Contributed Goods and Services 4,579,000 - 14%
General Management and Administration 4,456,000 - 13%
Guest and Member Relations 3,430,000 - 10%
Marketing and Development 3,692,000 - 11%
Depreciation 3,531,000 - 10%
Education and Conservation 2,531,000 - 8%
According to the Philadelphia Zoo's annual report for the year 2002, the number one expense of the Philly Zoo was "General Management and Administration," which accounted for over $5,000,000, NEARLY $800,000 MORE THAN THE ZOO's EXPENDITURES ON ANIMAL CARE THAT SAME YEAR.
http://www.philadelphiazoo.org/media/pdf/abu_pi_annual_report2002.pdf
http://www.philadelphiazoo.org/media/pdf/abu_pi_annual_report2003.pdf