1. A composition, a fluid, a bioreactor, a mud, a reservoir, a product of manufacture or a synthetic consortium comprising: (1) a plurality of microorganism strains, wherein the microorganism strains comprise: (a) at least two, three, four, five, six, seven, eight, nine, ten or eleven or all twelve of the microorganism strains of Consort-ABS1; or (b) a group (or “consortium”) of different microorganism strains comprising at least two, three, four, five, six, seven, eight, nine, ten, eleven or twelve different microorganism strains, each strain comprising at least one 16S rRNA gene or nucleic acid sequence selected from the group consisting of a nucleic acid having at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or 100% (complete) sequence identity to SEQ ID NO:1, SEQ ID NO:2, SEQ ID NO:3, SEQ ID NO:4, SEQ ID NO:5, SEQ ID NO:6, SEQ ID NO:7, SEQ ID NO:8, SEQ ID NO:8, SEQ ID NO: 10, SEQ ID NO: 11 and SEQ ID NO: 12, or (c) a group (or “consortium”) of different microorganism strains consisting of at least two, three, four, five, six, seven, eight, nine, ten, eleven or twelve different microorganism strains, each strain comprising at least one 16S rRNA gene or nucleic acid sequence selected from the group consisting of a nucleic acid having at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or 100% (complete) sequence identity to SEQ ID NO:1, SEQ ID NO:2, SEQ ID NO:3, SEQ ID NO:4, SEQ ID NO:5, SEQ ID NO:6, SEQ ID NO:7, SEQ ID NO:8, SEQ ID NO:8, SEQ ID NO: 10, SEQ ID NO: 11 and SEQ ID NO: 12, (2) the composition, a fluid, a bioreactor, a mud, a reservoir, a product of manufacture or a synthetic consortium of (1) wherein each member of the group (or “consortium”) of different microorganism strains is a different microorganism strain, or each member of the group (or “consortium”) of different microorganism strains has a different 16S rRNA gene or nucleic acid sequence; (3) the composition, a fluid, a bioreactor, a mud, a reservoir, a product of manufacture or a synthetic consortium of (1) or (2), wherein the at least one 16S rRNA gene or nucleic acid sequence comprises a subsequence (a portion) of a 16S rRNA sequence that optionally includes (comprises) the fifth and sixth variable (V5 and V6) regions of a 16S rRNA gene; (4) the composition, a fluid, a bioreactor, a mud, a reservoir, a product of manufacture or a synthetic consortium of any of (1) to (3), wherein the reservoir is an in situ subsurface reservoir, a surface reservoir, a synthetic reservoir or an excavated reservoir; or (5) the composition, fluid, mud, bioreactor, reservoir, product of manufacture or a synthetic consortium of any of (1) to (4), wherein: (i) at least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 or all 12 of the microorganism strains comprise a member of the genus Acetobacterium , a member of the genus Bacteroidetes and/or a member of the genus Spirochaetes ; or (ii) at least 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 of the microorganism strains comprise a member of the genus Acetobacterium , a member of the genus Bacteroidetes and a member of the genus Spirochaetes.