wonders what the effects of these changes are upon the entire marsh system. 

 Officials of the USFWS have estimated that more than 18 percent of the refuge's 

 19,764 ha (48,799 acres) "have been substantially modified by extensive criss- 

 crossing of access canals" (Gusey and Maturgo, 1972). 



In most instances, the right to explore for and produce petroleum on refuge 

 land has been beyond the control of the USFWS. Oil and gas development has 

 proceeded on wildlife refuges as a result of circumstances of land ownership. 



OWNERSHIP AND SURFACE RIGHTS 



The legal question regarding ownership is very complicated. In brief, 

 however, there are three circumstances that are found in coastal refuges: 

 Federal ownership, excepted oil and gas, and reserved oil and gas. 



Federally Owned Oil and Gas 



Federal ownership of oil and gas in refuges does not occur very often. 

 In a few cases, however, there is complete ownership of all land interests - 

 termed "fee simple absolute" - of at least some of the land tracts making up a 

 refuge. This land may be leased for minerals when the U.S. Geolgocial Survey 

 (USGS) has determined that the lands are subject to "drainage" (43 CFR 3103.3-1). 

 This term refers to the loss of petroleum from formations tapped by oil and 

 gas wells on adjacent lands. Otherwise, no leases for oil and gas may be made 

 on wildlife refuge lands where the U.S. Government owns all oil and gas interests 

 (43 CFR 3103.3-3). 



Where a determination is made by the USGS that lands are subject to drain- 

 age, the lands may be leased by competitive bid, and petroleum development may 

 proceed under the direction of the USFWS and the Bureau of Land Management 

 (BLM). Use of the surface lands by the petroleum exploration company is then 

 subject to the terms of the lease and the normal rights of ownership. On the 

 Sabine NWR, the U.S. Government believes it owns all land interests in the East 

 Cove unit, but the area's status is in litigation with a private mineral owner. 

 On the Delta NWR, the U.S. Government owns all interests on the western portion 

 of the refuge, and currently is leasing the oil and gas rights. 



Excepted Oil and Gas 



In many instances, a land owner may divide interests in his land as he 

 sees fit. For example, he may sell or lease his oil and gas interests (commonly 

 called the mineral estate). Separation of the oil and gas mineral estate may 

 be accomplished by an agreement with a third party, or by retaining ownership 

 of the minerals in a conveyance of the rest of the land (Hemingway, 1971). 

 For example, in 1924 the Texas Company sold the surface lands down to 61 m 

 (200 ft) on what was later to become the Sabine NWR to the Orange-Cameron Land 



