Looking at the DFG Reg website, it appears you can fish in the night time in Inyo County, but not Mono County:
3.00. Fishing Hours.
(a) Day Defined: One hour before sunrise to one hour after sunset. Remaining hours are night.
(b) All fish may be taken day or night, except as follows:
(1) WATERS WITH RESTRICTED FISHING HOURS FOR ALL SPECIES:
(A) American River between Business 80 and Nimbus Dam (Sacramento Co.): Night fishing prohibited
(B) Heenan Lake, (Alpine Co.): See Section 7.50(b)(76)(A).
(C) Mono County: Night fishing is prohibited in all Mono County waters except Topaz Lake, where fishing is prohibited from two hours after sunset to one hour before sunrise.
(D) Tahoe Lake (Placer and El Dorado Cos.): Fishing is prohibited from two hours after sunset to one hour before sunrise.
(2) WATERS WHERE NIGHT AND DAY FISHING IS ALLOWED, BUT NO TROUT OR SALMON MAY BE TAKEN AT NIGHT:
(A) North Coast District.
(B) North Central District, all waters except Berryessa Lake (Napa Co.) and Mendocino Lake (Mendocino Co.)
(C) South Central District, all waters except Coyote Lake (Santa Clara Co.)
(D) Valley District, north of Interstate 80, all waters except Camp Far West Lake (Nevada, Placer, and Yuba counties), Collins Lake (Yuba Co.), Oroville Lake (Butte Co.), and Wildwood Lake (Nevada Co.).
(E) Shasta, Siskiyou, Lassen and Tehama counties.
Does this mean you can fish South Lake, Sabrina, Rock Creek Lake at Night (since it's considered Inyo County per http://www.dfg.ca.gov/fish/Hatcherie...andDeserts.asp), but not Convict, Mammoth Lakes, June, Virginia, Twin Lakes Bridgeport which are in Mono County? Section 2 in the regulation wouldn't be applicable since all these lakes are in Sierra District.
Thanks!