I'm just starting to research the KENNA families in New Zealand due to new-found probable link with families in New South Wales, Australia, descendants from Irish peoples of Counties Tipperary and Kilkenny.

Births, Deaths & Marriages Online - New Zealand

MARRIAGES: 1840 to 1930

Grooms:
1922/5639 Marguerite Chapman Richard Lamington Kenna
1899/5057 Margaret Jane Lyon Percy Kenna
1922/4097 Margaret Jane McConnochie Robert George Webb Kenna
1916/13750 Margaret Jane Morgan Leonard George Kenna
1921/1013 Mary Ellen Murphy Robert Boyd Kenna

Brides:
1925/2974 Mona Ray Kenna Harold Miles
1914/3116 Muriel Helen Kenna Horace Leslie Callaway
1923/447 Mary Margaret Kenna James Brown
1901/1360 Catherine Kenna John Albert Rail
1877/3149 Mary M Kenna John Somers

BIRTHS: 1840 to 1960

1909/9760 Kenna Percy Jennings Margaret Jean Percy
1927/13262 Kenna NR Marguerite Richard Lamington
1925/9053 Kenna NR Marguerite Richard Lamington
1901/5667 Kenna Robert George Webb Margaret Jane Percy

DEATHS: 1840 to 2010

1973/32545 Kenna Ellen Mary 14 September 1894
1943/24312 Kenna Helen Williamson Ferguson 86Y
1943/24428 Kenna Percy 86Y
1974/29499 Kenna Robert Boyd 17 July 1894
1974/30689 Kenna Harold 14 December 1924
1943/27143 Kenna John 74Y
1999/24066 Kenna Ita Mary 18 March 1912
1976/27613 Kenna Percy Jennings 26 October 1909
1956/25793 Kenna Kerry Colin 8H
1954/35006 Kenna Timothy 70Y
1959/21044 Kenna Leonard George 79Y
1961/36271 Kenna Richard Lemington 80Y
1964/28684 Kenna Margaret Jane 84Y
1969/32698 Kenna Margaret Jane 93Y
1985/46323 Kenna Samuel Carleton 27 April 1918
1992/46422 Kenna Edward 18 April 1912
1924/1511 Kenna Richard Maurice 70Y
1926/307 Kenna Kathleen 24H
1907/413 Kenna Peter 74Y
2007/22995 Kenna Joyce Agnes 16 November 1924
1985/53947 Kenna Doris Annie 6 July 1894
1934/6199 Kenna Marguerite 36Y
1985/34918 Kenna Mary Eileen 26 March 1912

FamilySearch LDS database seems to have a great deal of KEENA records.